A Visual Guide to Version Control _ BetterExplained

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rsion Control (aka Revision Control aka Source Control) lets you track your files over time. Why do you

re? So when you mess up you can easily get back to a previous working version.

ouve probably cooked up your own version control system without realizing it had such a geeky name.

ot any files like this? (Not these exact ones I hope).

KalidAzadResumeOct2006.doc

KalidAzadResumeMar2007.doc

instacalc-logo3.pnginstacalc-logo4.png

logo-old.png

s why we use Save As. You want the new file without obliterating the old one. Its a common problem,

d solutions are usually like this:

Make a single backup copy (Document.old.txt).

If were clever, we add a version number or date: Document_V1.txt, DocumentMarch2007.txt

We may even use a shared folder so other people can see and edit files without sending them over

email. Hopefully they relabel the file after they save it.

o Why Do We Need A Version Control System (VCS)?

ur shared folder/naming system is fine for class projects or one-time papers. But software projects? Not a

ance.

o you think the Windows source code sits in a shared folder like Windows2007-Latest-UPDATED!!, for

yone to edit? That every programmer just works in a different subfolder? No way.

rge, fast-changing projects with many authors need a Version Control System (geekspeak for file

tabase) to track changes and avoid general chaos. A good VCS does the following:

Backup and Restore. Files are saved as they are edited, and you can jump to any moment in time.

Need that file as it was on Feb 23, 2007? No problem.

Synchronization. Lets people share files and stay up-to-date with the latest version.

Short-term undo. Monkeying with a file and messed it up? (Thats just like you, isnt it?). Throw away

your changes and go back to the last known good version in the database.

Long-term undo. Sometimes we mess up bad. Suppose you made a change a year ago, and it had a

bug. Jump back to the old version, and see what change was made that day.

Track Changes. As files are updated, you can leave messages explaining why the change happened

(stored in the VCS, not the file). This makes it easy to see how a file is evolving over time, and why.

Track Ownership. A VCS tags every change with the name of the person who made it. Helpful for

ual Guide to Version Control | BetterExplained http://betterexplained.com/articles/a-visual-guide-to-versio

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blamestorming giving credit.

Sandboxing, or insurance against yourself. Making a big change? You can make temporary changes in an

isolated area, test and work out the kinks before checking in your changes.

Branching and merging. A larger sandbox. You can branch a copy of your code into a separate area

and modify it in isolation (tracking changes separately). Later, you can merge your work back into the

common area.

ared folders are quick and simple, but cant beat these features.

earn the Lingo

ost version control systems involve the following concepts, though the labels may be different.

sic Setup

Repository (repo): The database storing the files.

Server: The computer storing the repo.

Client: The computer connecting to the repo.

Working Set/Working Copy: Your local directory of files, where you make changes.

Trunk/Main: The primary location for code in the repo. Think of code as a family tree the trunk is the

main line.

sic Actions

Add: Put a file into the repo for the first time, i.e. begin tracking it with Version Control.

Revision: What version a file is on (v1, v2, v3, etc.).

Head: The latest revision in the repo.

Check out: Download a file from the repo.

Check in: Upload a file to the repository (if it has changed). The file gets a new revision number, and

people can check out the latest one.

Checkin Message: A short message describing what was changed.

Changelog/History: A list of changes made to a file since it was created.

Update/Sync: Synchronize your files with the latest from the repository. This lets you grab the latest

revisions of all files.

Revert: Throw away your local changes and reload the latest version from the repository.

vanced Actions

Branch: Create a separate copy of a file/folder for private use (bug fixing, testing, etc). Branch is both a

verb (branch the code) and a noun (Which branch is it in?).

Diff/Change/Delta: Finding the differences between two files. Useful for seeing what changed between

revisions.

Merge (or patch): Apply the changes from one file to another, to bring it up-to-date. For example, you

can merge features from one branch into another. (At Microsoft this was called Reverse Integrate and

Forward Integrate)

Conflict: When pending changes to a file contradict each other (both changes cannot be applied).

Resolve: Fixing the changes that contradict each other and checking in the correct version.

Locking: Taking control of a file so nobody else can edit it until you unlock it. Some version control

systems use this to avoid conflicts.

Breaking the lock: Forcibly unlocking a file so you can edit it. It may be needed if someone locks a file

and goes on vacation (or calls in sick the day Halo 3 comes out).


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Check out for edit: Checking out an editable version of a file. Some VCSes have editable files by

default, others require an explicit command.

d a typical scenario goes like this:

ice adds a file (list.txt) to the repository. She checks it out, makes a change (puts milk on the list),

d checks it back in with a checkin message (Added required item.). The next morning, Bob updates his

cal working set and sees the latest revision oflist.txt, which contains milk. He can browse the

angelog or diffto see that Alice put milk the day before.

isual Examples

is guide is purposefully high-level: most tutorials throw a bunch of text commands at you. Lets cover the

gh-level concepts without getting stuck in the syntax (the Subversion manual is always there, dont worry).

metimes its nice to see whats possible.

heckins

e simplest scenario is checking in a file (list.txt) and modifying it over time.

ch time we check in a new version, we get a new revision (r1, r2, r3, etc.). In Subversion youd do:

svnaddlist.txt

(modifythefile)

svncilist.txt m"Changedthelist"

e m flag is the message to use for this checkin.

heckouts and Editing

reality, you might not keep checking in a file. You may have to check out, edit and check in. The cycle

oks like this:


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you dont like your changes and want to start over, you can revert to the previous version and start again

r stop). When checking out, you get the latest revision by default. If you want, you can specify a particular

vision. In Subversion, run:

svncolist.txt(getlatestversion)

...editfile...

svnrevertlist.txt(throwawaychanges)

svnco r2list.txt(checkoutparticularversion)

iffs

e trunk has a history ofchanges as a file evolves. Diffs are the changes you made while editing: imagine

u can peel them off and apply them to a file:

r example, to go from r1 to r2, we add eggs (+Eggs). Imagine peeling off that red sticker and placing it on

, to get r2.

d to get from r2 to r3, we add Juice (+Juice). To get from r3 to r4, we remove Juice and add Soup (-Juice,


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Soup).

ost version control systems store diffs rather than full copies of the file. This saves disk space: 4

visions of a file doesnt mean we have 4 copies; we have 1 copy and 4 small diffs. Pretty nifty, eh? In SVN,

e diff two revisions of a file like this:

svndiff r3:4list.txt

iffs help us notice changes (How did you fix that bug again?) and even apply them from one branch to

other.

onus question: whats the diff from r1 to r4?

+Eggs

+Soup

otice how Juice wasnt even involved the direct jump from r1 to r4 doesnt need that change, since Juice

as overridden by Soup.

ranching

anches let us copy code into a separate folder so we can monkey with it separately:

r example, we can create a branch for new, experimental ideas for our list: crazy things like Rice or Eggo

affles. Depending on the version control system, creating a branch (copy) may change the revision number.

ow that we have a branch, we can change our code and work out the kinks. (Hrm waffles? I dont know


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hat the boss will think. Rice is a safe bet.). Since were in a separate branch, we can make changes and test

isolation, knowing our changes wont hurt anyone. And our branch history is under version control.

Subversion, you create a branch simply by copying a directory to another.

svncopyhttp://path/to/trunkhttp://path/to/branch

branching isnt too tough of a concept: Pretend you copied your code into a different directory.uve probably branched your code in school projects, making sure you have a fail safe version you can

turn to if things blow up.

erging

anching sounds simple, right? Well, its not figuring out how to merge changes from one branch to another

n be tricky.

ts say we want to get the Rice feature from our experimental branch into the mainline. How would we do

is? Diff r6 and r7 and apply that to the main line?

rongo. We only want to apply the changes that happened in the branch!. That means we diff r5 and r6,

d apply that to the main trunk:

we diffed r6 and r7, we would lose the Bread feature that was in main. This is a subtle point imagine

eeling off the changes from the experimental branch (+Rice) and adding that to main. Main may have had

her changes, which is ok we just want to insert the Rice feature.

Subversion, merging is very close to diffing. Inside the main trunk, run the command:


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svnmerge r5:6http://path/to/branch

is command diffs r5-r6 in the experimental branch and applies it to the current location. Unfortunately,

bversion doesnt have an easy way to keep track of what merges have been applied, so if youre not careful

u may apply the same changes twice. Its a planned feature, but the current advice is to keep a changelog

essage reminding you that youve already merged r5-r6 into main.

onflicts

any times, the VCS can automatically merge changes to different parts of a file. Conflicts can arise when

anges appear that dont gel: Joe wants to remove eggs and replace it with cheese (-eggs, +cheese), and Sue

ants to replace eggs with a hot dog (-eggs, +hot dog).

this point its a race: if Joe checks in first, thats the change that goes through (and Sue cant make her

ange).

hen changes overlap and contradict like this, the VCS may report a conflict and not let you check in its

to you to check in a newer version that resolves this dilemma. A few approaches:

Re-apply your changes. Sync to the the latest version (r4) and re-apply your changes to this file: Add

hot dog to the list that already has cheese.

Override their changes with yours. Check out the latest version (r4), copy over your version, and

check your version in. In effect, this removes cheese and replaces it with hot dog.

onflicts are infrequent but can be a pain. Usually I update to the latest and re-apply my changes.


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agging

ho would have thought a version control system would be Web 2.0 compliant? Many systems let you tag

abel) any revision for easy reference. This way you can refer to Release 1.0 instead of a particular build

mber:

Subversion, tags are just branches that you agree not to edit; they are around for posterity, so you can see

actly what your version 1.0 release contained. Hence they end in a stub theres nowhere to go.

(intrunk)

svncopyhttp://path/to/revisionhttp://path/to/tag

eal-life example: Managing Windows Source Code

e guessed that Windows was managed out of a shared folder, but its not the case. So hows it done?

Theres a main line with stable builds of Windows.

Each group (Networking, User Interface, Media Player, etc.) has its own branch to develop new

features. These are under development and less stable than main.

u develop new features in your branch and Reverse Integrate (RI) to get them into Main. Later, you

orward Integrate and to get the latest changes from Main into your branch:


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Tweet 35 9

ts say were at Media Player 10 and IE 6. The Media Player team makes version 11 in their own branch.

hen its ready and tested, theres a patch from 10 11 which is applied to Main (just like the Rice example,

t a tad more complicated). This a reverse integration, from the branch to the trunk. The IE team can do

e same thing.

ter, the Media Player team can pick up the latest code from other teams, like IE. In this case, Media Player

rward integrates and gets the latest patches from main into their branch. This is like pulling in the Bread

ature into the experimental branch, but again, more complicated.

its RI and FI. Aye aye. This arrangement lets changes percolate throughout the branches, while keeping

w code out of the main line. Cool, eh?

reality, theres many layers of branches and sub-branches, along with quality metrics that determine when

u get to RI. But you get the idea: branches help manage complexity. Now you know the basics of how one of

e largest software projects is organized.

ey Takeaways

y goal was to share high-level thoughts about version control systems. Here are the basics:

Use version control. Seriously, its a good thing, even if youre not writing an OS. Its worth it for

backups alone.

Take it slow. Im only now looking into branching and merging for my projects. Just get a handle on

using version control and go from there. If youre a small project, branching/merging may not be an

issue. Large projects often have experienced maintainers who keep track of the branches and patches.

Keep Learning. Theres plenty of guides for SVN, CVS, RCS, Git, Perforce or whatever system youre

using. The important thing is to know the concepts and realize every system has its own lingo and

philosophy. Eric Sink has a detailed version control guide also.

ese are the basics as time goes on Ill share specific lessons Ive learned from my projects. Now that

uve figured out a regular VCS, try an illustrated guide to distributed version control.

ther Posts In This Series

A Visual Guide to Version Control (This post)1.

Intro to Distributed Version Control (Illustrated)2.

Aha! Moments When Learning Git3.


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24 thoughts on A Visual Guide to Version Controlngback: Visual guide to version control Dyans Weblog

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ngback: The Abarentos Narrative links for 2007-09-28

ngback:joet3ch.com Version Control

ngback: links for 2007-09-28 at graemef.com

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ontrol - Subversion/SVN

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cialsoftware, socialnetworking Internet Duct Tape

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ith Phil Gainley

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ngback: links for 2007-12-13 at DeStructUred Blog

ngback: Backups Bhushan G Ahires Weblog

1 6

1

hare what worked: Aha moments & FAQ

t's create a living reference for how best to understand this topic.

the whole part! (More...)

Branches and how they are merged.


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ngback: Principle #1 - Builds should be repeatable (Part 2) Sauers

chnologies

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ngback: Mind Gravy Blog Archive links for 2008-01-24

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etworking and Subscriber-based Services.

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esigner

Carlton Dickson

on September 28, 2007 at 12:44 am said:


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I absolutely love a Friday but this article has made my day already!

Thanks for putting this togethergoing to have a read of this later on

today.

C

Carlton Dickson


Great article Khalid, and thanks for the link to Erics articles, they

were pretty good too!

I will be testing the tagging and branching approach you both

mention, it will mean I can check out a branch (i.e. previous release)

into a new foldermake bug fixes and check it back into the branch

and deploy to live server in a more controlled, and traceable way.

Then would obviously need to merge bug fixes into my current trunk

(development work since last version).

Here is quite a useful resource for SVN and source control in general

by the way http://svnbook.red-bean.com/

Kalidon September 28, 2007 at 9:04 am said:

Hi Carlton, thanks for dropping by! Yep, Im working out my own

branching/merging scheme to make it easy to edit/update the live

version while still doing new development. Let me know if you have

any insights

Hi Mark, thanks for the comment and link I hadnt seen that SCM

before.

Skid Vis


Wow.. you are a breath mint!

A Life-saver to be exact.. Ive been looking for something like this for

day..


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Thanks!

Tony


That was very tasty. Thank you.

Kalid


Thanks guys! Not sure whats happening with the food theme

(lifesavers, tasty articles) but Im happy to oblige

(EDIT: Wow, I had been re-reading the article so many times that I

forgot food items were the examples I used! They just became a

series of words to me.)

Amit


Great Read

Kalid


Thanks Amit, glad you liked it.


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Kevin

on September 28, 2007 at 12:10 pm said:

Great article. Just curious what tool you used for diagramming.

Mario


thanks for the outline. really helped me grasp the fundamentals.

karim


Im using svn thats more than a year now and I love it. Thanks for

that refreshing tuto, it makes its learning for the novice a real

pleasure

Tiago Serafim


Nice article.

May I ask where did you do that neat graphics?

Thanks,

Kalid


Hi all, thanks for the comments. Ack, you want to know the secret

sauce? Microsoft Paint.

Just kidding . I make the diagrams in PowerPoint 2007, by drawing


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various shapes, arranging and styling them appropriately. If you like,

check out this article:

http://betterexplained.com/articles/an-intuitive-guide-

to-exponential-functions-e/

and the corresponding PowerPoint file:

http://betterexplained.com/examples/graphics/Exponential-

growth.pptx

Kayan


yes, Ive the same question (that caused a-ha moment ) what tool do

you use to make such a nice web2.0ish graphics ?

Thanks

Kalyan

venki


fabulous read, Thanks tons for putting this together

Kalid


@Kalyan: I used PowerPoint 2007 theres more details in comment

#14, above.

@venki: Thanks for the comment, it was a lot of fun to write.

Sam Jones



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Great post! Thanks for doing this.

Kalid


Thanks Sam, youre more than welcome.

Ed


Thank you for your wonderful effort.

Kalid


Hi Ed, thanks for the support.

Carlo


Is there a VCS that doesnt require a server environment? Something

that I can use with Visual Studio 2005 for C#

brian


Great detail of how the version control works. Thanks for time to put

this together.


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20/54

Kalid


@Brian: Thanks, glad you liked it!

@webmat: Great tips, thanks for sharing! (This is exactly what I

hoped would happen people sharing their personal tips, tricks and

favorites).

@Carlo: Try out webmats suggestions. I know Visual Studio has

plugins for various VCS systems like SVN, they may have Bazaar or

Mercurial as well. This makes it easy to see the status of the project

you are working on, inside of Visual Studio.

Anonymous


While this looks like a nice introduction to the CVS and SVN model of

version control, its pretty specific to this model.

The All version control systems involve the following concepts part

is certainly false unless you exclude distributed version control,

systems that dont directly track files (eg Git), systems that dont use

revisions (eg Darcs), and probably other categories.

Kalid


Hi, thanks for the feedback. Yes, this guide was meant to give an

intro to the most common VCS concepts. I wasnt that familiar with

distributed and other systems, but it seems they can have different

behavior I may do a follow up on them. Till then, Ill caveat the

sentence with Most vs All .


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Gareth

on October 1, 2007 at 1:08 am said:

Thanks this is great for non tech folk

dextrous


Hi,

Its awesome, I have already recommended to all newbies around me

to refer it.

good stuff. How about writing same thing for a distributed version

control.

shawn


thanks for this great tutorial. Makes a lot of sense really quick.

Kalid

on October 1, 2007 at 2:51 pm said:

Gareth and shawn, thanks for the comments. Im thrilled when

concepts can shine through, I really believe any subject should be

made sensible to everyone

Dextrous, I dont know much about distributed version control

systems, but am excited to learn about them. Id love to write moreonce I figure them out.


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Sagar Mehta


very well explained indeed !!!!

Kalid


Thanks Sagar, glad it was useful for you.

Sagar Mehta


The content is good, but I was more impressed with the simplicity

with which it is presented

A lot to learn for potential tutorial writers

Kalid


Thanks Sagar I find it helps to relate new material to what people

already know (like versioning their files by changing the filename).

Eventually Id like to do a tutorial on how to do a tutorial

Tanya


thank you for the article! Ive used CVS for 2 years, but Ive got clear

understanding of branches and merging only now

Kalid


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Great Tanya, Im glad you found it useful!

Neville Franks


Kalid, very good intro article. I wrote Get up and running with

TortoiseSVN and Subversion in 15 minutes a while back which will be

of interest to folks starting out with SubVersion. You can find at:

http://blog.surfulater.com/2007/02/28/get-up-and-running-

with-tortoisesvn-and-subversion-in-15-minutes/

Kalid


Hi Neville, thanks for dropping by. This article was about the high

level concepts, so its nice to learn how to set up the nitty-gritty

Paul Ziakin

on December 14, 2007 at 3:05 pm said:

Found this article while hunting for a useable distinction between

Document Version and Document Revision. Any takers out there?

Kalid


Hi Paul, unfortunately the words version and revision seem to be

used interchangibly in the sources Ive found. It might depend on the

particular version/revision control tool you are using .


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Dan

on January 25, 2008 at 7:20 am said:

Great post! Using straight to the point explanations, attractive visual

aids, and command-line examples really helped make the

fundamentals easy to understand!

Great work!

Kalid


Thanks Dan! I try to use as many techniques as I can (diagrams,

text, etc.) since people learn differently. Glad it worked for you!

Ferdinand

on February 17, 2008 at 8:28 am said:

Thanks man, this is an excellent primer, just what I needed !

Kalid


Thanks Ferdinand, glad it worked for you.

user

on March 25, 2008 at 12:47 am said:

please, if possible, add a visual guide (picture/diagram) for concept of

conflict.

Nicolas Hoizey


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Great article!

Being a user of CVS and SVN for years, I always have some

difficulties trying to explain it to my collegues and friends, it will help

me a lot!

May I translate it into french and publish it on my weblog, with a linkto your original?

Kalid


Hi Nicolas, thanks for the comment, glad you enjoyed it. Sure, you

can translate it, thanks for asking.

MB

on April 28, 2008 at 6:26 pm said:

well explained, i like the use of diagrams. The presentation also looks

very professional, thanks!

Kalid


Thanks MB!

Dave

on April 29, 2008 at 5:54 am said:

*T*H*A*N*K*S*


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Kalid


Hi Dave, youre welcome .

FHierro

on May 17, 2008 at 9:15 am said:

Yeah, guys! CVS is a very useful tool for any of you who works with a

single file during a long time while building its definitive content.

However, CVS has the inconvenient of expecting to be you (the user)

the one who carries out the check-in and check-out operations.

I have found a very important tool name Live!Doc Personal Edition(www.mylivedocuments.net) which automatically carries out check-in

operations and transparently keeps all the changes done in any of

your files.

I suggest you to test it

Ambaron May 30, 2008 at 9:46 am said:

amazing read! great job!

Kalid

on May 30, 2008 at 10:04 am said:

Thanks Ambar, glad you liked it!

Dilan

on June 5, 2008 at 9:43 pm said:

THE BEST GUIDE FOR VCS Ive seen.. Great great stuff. thanks a


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billion

Kalid


Thanks Dilan, youre welcome!

ggyy_sun


What a nice paper!

Kalid

on June 10, 2008 at 11:11 am said:

Thanks, glad you enjoyed it.

Bedrich


Great article, really good for a version control newbie like myself.

Kalid


Thanks Bedrich, glad it was helpful.

Rob

on July 2, 2008 at 10:53 am said:


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Excellent job! One suggestion though

Ive always used a visual diff program so I was confused for a while

on your explanation of the diff process. I think it would help if you

pointed out that diffing r6 with r7 would generate:

+rice

-bread

That is, the diff things you deliberately removed bread. How could it

know the difference?

So, when were ready to merge we want to know the difference

between the file we started with on our branch and the final version

on our branch. Then we merge those differences with the latest

version on the trunk.

Something like that. A bit more theory of what were trying to do.

This really helped me solidify the process in my head. Thanks,

Peace,

Rob:-]

Tim

on August 31, 2008 at 1:33 am said:

Who would have thought a version control system would be Web 2.0

compliant? Many systems let you tag (label) any revision for easy

reference

Please, this is not remotely like folksonomic tagging in the Web 2.0

sense. If this is a joke, its going to confuse the heck out of people

whove not encountered version control before.

Scartaris


This is a great introduction to VCS! Source code management can be

so complicated to explain, but you have made it quite clear.

I would like to see a similar explanation of distributed VCS systems.

I have read about them, but I have not been able to make any sense

of them they seem like trying to play volleyball when every player


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has her own ball. I dont see how it can possibly be anything other

than a cluster-you-know-what. But they obviously work for some

projects, and I would really like that explained.

Scartaris


Oh! There is a link to an explanation of distributed version control

right at the end! Thanks!

Ammar


Thank you very much for this great resource I will definitely point it

to my colleagues so that they learn about source control.

Much thanks!

Kalid

on November 18, 2008 at 1:23 am said:

@Scartaris: No problem, glad you found it.

@Ammar: Glad you enjoyed it!

Jeff


Thank you! This is good stuff. -j

Rythums

on December 8, 2008 at 12:00 am said:


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It was very helpful

I have a question

In any of the file header say a *.c file I want to maintain the

comments of commiting is it possible to do that automatically?

by putting a directive as

or something similar ?

for example, have a file header as

// file name : xxx.c

// auther : xyz

// creation date : dd mm yy

// revisions : date comment

// 1.0 : dd-mm-yy base version

// 1.1 : dd-mm-yy trying auto-version

// :

thanks in advance

ryth

Kalid


@Jeff: Youre welcome.

@Rythums: Offhand, I dont know of a simple way to prepend the

comments to the file (ironically, that would make the file have a newrevision, right?). In general, the source control system should

probably be used to view the log/history of a file.

Tracy


This is fantastic. Ive been interested in using version control at the

office but Im pretty sure our IT team thinks its not worth it for my

needs (more along the lines of grocery lists than software

development). Do you know of any program that does this sort of

thing at a more basic level, for everyday users?

Love the site, great idea.


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Manish


It is such a treat to read a documents like this. Kalid, you rock!!

Kalid

on February 13, 2009 at 5:30 pm said:

@Tracy: Thanks for the comment. Subversion is probably the

simplest system to use (it has plugins like TortoiseSVN for Windows so

you dont need to use the command line).

@Manish: Thanks!

imissmyjuno

on March 4, 2009 at 12:03 pm said:

Thanks for this! I understand the topic but havent found a better

guide yet. So many times I tried to explain the concept and havent

succeeded in doing so. Ill try this guide next time.

brad


This is great for the concepts but for a newbie, im a little lost

without an ab initio. i write web code, never use the command line,

and am not sure if there is a software like subversion that is assumedto be in use?

Kalid


@imissmyjuno: Youre welcome!


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@brad: Thanks for the comment I realize I forgot to mention the

examples were for Subversion! (Ill update that now). The key

principles, pros and cons, and diagrams should apply to most

traditional version control systems like Subversion, CVS or RCS.

Walter


Kalid,

Many thanks. Im a small projects guy who has been wavering about

using vcs for a while, and this tipped me toward using it.

Kalid


@Walter: Youre welcome hope it works out for you!

adi


most appreciated. u v got a great way of explaining concepts in a

simple way. Thank u a lot n i wish u a lot of luck!

adi

Catherine

on May 10, 2009 at 11:56 pm said:

Good article. Thanks.

Catherine Sea

http://www.scmsoftwareconfigurationmanagement.com/


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sfasdf


afasdfasdf

Shyam


Good article

webCV


Excellent article! Thanks for this fantastic article which

explains(better! with clear diagrams, how VCS works Done a bit

of digging and SVN seems the way to go. Glad theres a plugin for

quanta plus since I use that for PHP. Again, thanks for an awesome

article Kalid.

Kalid


@webCV: Youre welcome!

Ranu Mandan

on August 3, 2009 at 7:28 am said:

that was the most simplest of all

thx for sharing


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Kalid

on August 6, 2009 at 7:46 pm said:

@Ranu: Thanks!

Ramesh


Thanks very much for sharing. I have been looking for an article like

this

Kalid


@Ramesh: Youre welcome!

Niks


Kalid,

Can I reuse the pictures (copy) to our folks in a PPT or something??

Kalidon August 19, 2009 at 8:53 pm said:

@Niks: Sure thing, but please include a reference back to the site.

Thanks!


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Kavin


Sir, it was very useful to know the basics of how one of the largest

software projects is organized.

Kalid


@Kavin: Glad you found it helpful!

skmwenda


Great stuff!now i fully get branching, and when to use RI or FI.

Kalid


@skmwenda: Thanks, glad it helped!

S M Nabeel Dibaji

on November 4, 2009 at 10:43 pm said:

Awesome post.

Really nice and easy to learn Source Control Concepts from the

scratchLOve U buddy

Deependra Solanky



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Great article for beginners. Thanks.

Kalid


@S M, @Deependra : Glad you liked it!

joy


Excellent! Thank you!

Kalid


@joy: Youre welcome!

Km


Lovely guide. No prob in understanding at all.

maverick


thanks for the post, its really helpful


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Have a question? Know an explanation that caused your own a-ha

moment? Write about it here.

Windows Linux Admin


Amazingly well explained. Im sending this to the non softare guys at

work


Excellent! Thank you!

sujith

on May 24, 2010 at 11:06 pm said:

Woderful !! thank You !!!


That is really a good guide! Very easy to understand and helpful. I amhaving less fear to the version control things at least, haha. Thanks

very much!


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Kalid

on May 31, 2010 at 10:30 pm said:

@: Yoiure welcome, glad it helped!

Bernard


I was looking for a user guide to version control. This is really an

excellent introduction.

Kalid


@Bernard: Thanks!

Rob Langley


hi I know this sounds like a tall order but does anyone know of a

VCS that would deal with the entire origination process, please? (ie,

pulling in all sorts of different source files text, Word, EPSs, TIFs,

pegs then through Quark/InDesign and through to PDF)

thanks

Rob

Kalid

on July 2, 2010 at 10:37 pm said:

@Rob: I think your best bet would be to use VersionCue or some

software designed just for the various Adobe formats most generic

VCS systems are optimized to working with plain text files.


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Josh Colter


Great high-level SVN overview. Love the visuals!

Appan


Very informative and detailed note on VCS.

Is it an individual contribution or an organisations contribution ?

whoever did it, thank you so much.

Ap

Kalid


@Appan: Thanks, glad you liked it! Yep, this was just a personal post,

not part of an organization.

Raj


Its cool, i have read some part and seems good

m4niac


Ive just started out to read the tutorial and I already want to tell you

I felt in love with this whole new VCS stuff . Thanks for that! And

of course, for this amazing tutorial.


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michael kenner


Absolutely Great. A credit to the author Kalid Azad. Very interesting

and very easy to follow!

Kalid


@Michael: Thank you, glad it helped!

ss


good article

Anonymous


wow! i have never come across any read(specially in IT) which was

so easy to understahnd.

i was LOL looking at the words like, blamestorming and

monkeying.Absolutely loved it.

It truly is better explained.

keep up the good work.

Cheers!!

Kalid


@Anonymous: Thanks! Yeah, theres no reason guides have to be dull

nobody wants to read (or write) that .


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Aya


WOW !! that was amazing and so simple indeed .. Im a third year

student in FCI and I have a presentation about VCS and I gotta tell

you that ur article was more than helpful to me .. thanx alot .. great

effort


LOL looking at the words like, blamestorming and

monkeying.Absolutely loved it.

sakhunzai


simply superb !

Anonymous


thanks a lot for this work, we will wait many from u

Anonymous


Thanks you for explaining the basic principals it makes things more

clear to me and will help me in fixing the way I set my VCS up and

maintain it in the future.


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Kalid


@Anonymous: Youre welcome!

Catherine


very illustrative content

Kalid


@Catherine: Thanks, glad you liked it.

Jorge Contreras


Hey ! this is a very good article. I had tried to understand version

control, I didnt know where to start, luckily I found this. Its simple,

useful. Nice job!

Pawankumar Jajara


Hi,

It was an awesome article on Version Control System. I have an

interview on monday and less time to look around, but your

information made my day. Its the best article I ever saw on VCS

Hats Off !


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Kalid


@Pawankumar: Thanks!

Michelle

on May 5, 2011 at 8:59 pm said:

Wow, this article really gives me a fantastic idea of what version

control is all about!!Great job!

Kalid


@Michelle: Thanks!

on May 21, 2011 at 10:24 pm said:

ow, this article really gives me a fantastic idea of what version control

is a

sports management course


betterexplained.com has been helping me and my college friends with

our school projects.

Mohnish Thallavajhula



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Pretty kewl. Stands up to the name- BetterExplained

Kalid


@Mohnish: Thanks .

Denim Geek


I actually wrote something very similar to this for my dissertation a

few years ago. Great article, well done on explaining this a lot clearer

than i could

Kalid


@Denim Geek: Appreciate the comment!

rosy


hello people i fell really helpful with this data provided..actually VCS

is my research topic so..i was just thinking that if u could send me

some more contents over VCSit will be very very helpful to mebdw thanx a lot kalid:)

raj



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good stuff mate..!!!!

Michael


What a great resource, and so well written. Thanks Kalid.

Kalid


@Michael: Thank you!

Khaled


Thanks man, it was very helpfull

Kalid


@Khaled: Youre welcome!

Ilana Gannetti


We are a gaggle of volunteers and starting a brand new scheme in

our community. Your web site provided us with valuable info to work

on. You have performed an impressive task and our whole

neighborhood can be grateful to you.


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Saleh


It is definitely Better Explained. Now, is there a GUI instead of

command line?

Thanks for the beautiful explanation.

Kalid


@Saleh: Glad you liked it! . Yep, there are GUI tools for SVN like

TortoiseSVN.

Vishnu Kumar


Hi KalidAn interviewer asked me this question..

If there are 55 versions of a file available55th one is the latest

onedeveloper checked out the 50th version and do some

modification and then check inwhat will be the new versioni

replied56thi think it was 51th

What would be the answer ?

Vishnu

kalid


@Vishnu: Thats a strange question, I think the interviewer may have

been misinformed about how version control works. Normally you

dont ask what is the version number as version control takes care

of that for you, and you dont revise old versions, you only add new

ones (a revised old version becomes a new element).


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Sole42


Great article.

I wish there were free CVS/SVN systems that actually do what they

are supposed to.

I tried 5 different free ones, including Tortoise which especially

doesnt work as advertised.

Havent tried commercial ones yet but I bet theres at least one worth

the money.

kalid


@Sole42: Thanks. Yes, some interfaces arent as clean/easy as others

I prefer using the command-line just because its consistent / easy

to use once youve learned it.

Amit


Thanx kalid!!!! It helped me so much to get basic ideas very easily

Nice technique to present the complex information in simple way

Simply great!!! I am beginner for Source Code Control and hope

that u help me to get myself deeper into this concept

thnx again

Hemangon December 23, 2011 at 9:05 pm said:

Great work ! Thanks a lot !

abbey


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Now thats a systematic approach of doing things. Thank you for the

post sir, keep posting more of your nice articles. Thanks

kalid


@Hemang: Youre welcome!

kalid


@Amit: Thank you, glad it helped!

Karen


Great post! Using straight to the point explanations, attractive visual

aids, and command-line examples really helped make the

fundamentals easy to understand!

Awesome work!

kalid

on January 9, 2012 at 1:34 pm said:

@Karen: Thank you!

Dich Vu Thiet Ke Web Uy Tin - Chat Luong - Chi Phi

Hop Ly


Pretty great post. I just stumbled upon your weblog and wished to


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mention that I have truly loved browsing your blog posts. After all I

will be subscribing to your rss feed and I hope you write again soon!

Amit


You are simply awesomegreat article.explained everything.

kalid


@Amit: Glad it helped!

Vijayakumar


Thanks for this wonderful work.

kalid


@Vijayakumar: Glad you liked it!

Papoj


Thank you for the post! It is very helpful since the beginning that you

make connection with the simple idea of version control system by

renaming files (so I feel familiar and ready to read what you will

write later on). The visual explanation is great, and the

accompanying SVN commands are even more helpful. May I ask you

to add the comparison with Git as well? I am learning Git and any

comparison like (commit in git = merge in svn) would be perfect.


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Thank you very much!

kalid


@Papoj: Thanks for the note! Yes, I have a guide on distributed

systems (http://betterexplained.com/articles/intro-to-distributed-

version-control-illustrated/) and some git tips

(http://betterexplained.com/articles/aha-moments-when-learning-

git/). Thanks for the feedback, its helpful to know what techniques

are working. I find one of the best ways to explain a new concept is

to relate it to what were already familiar with.

Emilio


kalid, what kind of license has this article? I want to translate parts of

it into spanish, for educational uses (very-first course in university). I

dont need all the information here, only the big ideas, and you have

one of the best explication Ive found.

kalid


@Emilio: Feel free to translate and use the article for educational use!

Just please include a reference back to the original. Thanks!

Deepak


Hi Kalid, thatnks for this nice visual article.Now I git it ..keep the

good work going.

kalid


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@Deepak: Thanks!

Emilio


Kalid, Thank YOU! I will put the source. If you want, you can send an

email, when the document is finished, I could send you a copy. Do

you use visio for the graphics? I think Ill use libreoffice draw.

kalid


@Emilio: Youre welcome! Sure, itd be fun to see the article when

youre done. I use Powerpoint 2007 for the graphics.

ANdrew


Great stuff, your article explains version control very nicely!

I like that youve used a combination of methods to explain the

concepts, and havent posted large blocks of svn/git/hg commands!

Stephen


Thanks a lot!! I have heard about version control for ages but never

really understood till I read your article!

kalid



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@Stephen: Awesome, glad it helped!

@Andrew: Thanks, appreciate it. Definitely, just throwing a chunk of

text commands at someone doesnt convey the intuition behind it all.

Peter Drinnan


Just wanted to point out that if you are on Windows, the new

GitExtension package includes everything you will need to setup

msysGit and the configuration works with TortoiseGit too. May save

you some time.

http://code.google.com/p/gitextensions/

brighteyes27

on May 22, 2012 at 10:10 am said:

Thanks Kalid, the write-up was done well. I have a much better

understanding on the Version Control concept. The visual examples

were very helpful and sealed the knowledge in my brain. Thanks

again!

kalid

on May 22, 2012 at 12:35 pm said:

@brighteyes27: Awesome, glad it helped!


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Robbie


I was struggling to understand version control and then I found this

and it was so clear and concise that it helped me to understand what

is being stated about it.

Thanks

Jommar


It helped me to understand the functionality and the usage of the

VCS. Thanks

kalid


@Jommar: Thanks, glad it helped.

ann


Very good explanation. Thanks

Kaviraj R


Is there any standards to follow for version numbers? that is V1, V2,

V3.. and V1.1 V1.2, V1.3.

how to decide which number system to use.

if i use v1.1,v1.2 v1.9 what is next? is there any specification to

choose V1.10 or V2.0.


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kalid


@Kaviraj: No official standards, but its usually

MajorVersion.MinorVersion. So if its a small upgrade, you only

increment the minor version. v1.0 to v1.9 to v1.10 to v1.11. Note

that v1.10 and v1.1 look similar, so its best to skip 1.10 and go

to 1.11.

Vee


A fantastic article for every type of user typically. This help out in lot

of concept and situations.

Thanks

Bunnynew


Hi,

I recently started using Apache VisualSubversion. We are testing in

Standard Free Edition. It is working nicely. My Developers want that,

instead of committing in Repos directly, it should be passed via an

Admin.

To be clear, if they do any changes in source file, it should be notify to

an Admin user. That admin user should be able to commit in Repos

after reveiwing the changes in source file.

Is this possible as I didnot find anything in visualsubversion ?

Is there any other product to achieve this ?

Thanks.


A Visual Guide to Version Control _ BetterExplained

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