Post on 25-Feb-2016
description
INTERNET LITERACY
&WEB SEARCHING
BASICS
WEB SEARCHING BASICS
The Internet is… a major presence in our daily lives constantly growing helping make an enormous amount of
information available
Browsers & Search Engines
Browsers are software that allow you to look at Internet content.Firefox, Google Chrome, Internet Explorer, Opera, Safari,
etc.
Search Engines are programs that allow you to “search” the Internet.Top 5 Search Engines:
○ Google, Yahoo!, Bing, Ask, AOL Search Top 5 Meta Search Engines
○ Dogpile○ Clusty○ Mamma
Top Web Sites…according to Google Uses popularity to rank web sites Counts the number of links from sites all
around the WebFor Example: If a large number of sites have a
specific keyword somewhere on their website along with a link to a particular site, Google counts the number of times the keyword appears along with the number of links to a particular site. The higher number of links to a site, the higher Google will rank that site on a list of results.
Top 5 Web Sites Are: Facebook Yahoo Live.com Wikipedia MSN
More about Search Engines They only search a TINY section of the
web and index it.
Search Engines have three basic functions:SearchStoreDeliver
Search Uses spiders, robots or
webcrawlers Software programmed by
the search engine to follow links and to gather information
Goes to only selected parts of the Internet scanning for text, links, and the URL
It then builds a list of words & where to find them
Store Search Engines create a list of
keywords & where to find them in an index
Each Engine creates guidelines to determine what is stored
Indexes for different search engines will not store the exact same information
(so it’s a good idea to use more then one search engine)
Deliver (Give results) Search Engines match the keywords of the user to
the keywords in the index Produces a ranked list of websites, web documents Each search engine uses a different set of rules for
ranking the results
So…
When you use a search engine, you are not searching the current web…
But rather the index created by the search engine to organize the information previously collected by the spider.
So what are you missing? Everything that isn’t on the
surface. The deep Web is about 500
times bigger than the surface Web.
The Deep Web is all information that is inaccessible through search engines. This would include private
databases, like the ones the library subscribes to through Galileo.
Types of Searches Index Searches (Directory) Natural language Searches Concept/keyword Searches
There are other types. For example some searches use more then one search engine to improve”hits”. This is called a Meta-Search engine. One example http://www.clusty.com
Index Searches A Directory of cataloged, hierarchically,
structured lists of web sites, like the yellow pages of a phone directory. Good for broad topics, the big picture, top down. (search for “online mortgages”). Limited web site inclusion and not good for complex or specific concept/keyword searches.
Typically these are evaluated for popularity, content and/or quality before being included
Example:http://www.yahoo.com/ Then check directory on left side
Try Yahoo and search for information about Chocolate
Natural language Searches A directory of possible questions. Good for
frequently asked questions, use on simple questions, -least comprehensive in sites included in search
Creators developed general question structures that can be asked about a topic
A question is typed into the question box, possible alternative statements of the question are then given, followed by links for possible answers. Example:
http://www.ask.com/
Try Ask Jeeves and ask for information about Chocolate
Concept/Keyword Searches Structured to the user as a traditional library database. Good for specific
searches e.g “stain removal” and complex esoteric topics e.g. “multiple melanoma”. Not good for top down general searches. Google at last report indexes the most web pages of all search engines.
“Bots” search the web for concepts/keywords picked by web site creators. Most organize the sites in terms of relevance as determined by links to a site and/or actual frequency of access of a web page, “hits”.
Concepts/keywords are typed into the query box using Boolean logic and the search engine’s rules to limit the list to the most relevant.
Example: www.google.com
Try google and search for information about Chocolate
Improving Searches using Logic with Google Describe your search as completely as possible to focus
returned links-- normally don’t capitalize (e,g a search for carnivore obtains a game, a type of animal and an FBI program, so specify
your term)
history of chocolate
Add quotes to limit search to those sites with this specific phrase:
“history of chocolate”
Limit search to non commercial sites:“history of chocolate” -.com
Check other rules of the search engine for focusing your search
On Google Choose “advanced search”
Refine Your Search I
Most search engines have an advanced search similar to Google’s. Check them out!
Boolean Logic for Searches AND---requires both terms
chocolate AND history
OR-----finds either termchocolate OR Hershey
NOT---excludes termchocolate NOT mars
Nested Boolean Searcheschocolate AND [diet OR health]
How Boolean is used in advanced search on one engine:
Refine II.The exact syntax for logic varies with the search engine. On Google for example click Advanced Search to make choices. Review Search Logic at:
http://www.internettutorials.net/boolean.html ORhttp://www.lib.csub.edu/infocomp/search/foundation.html
Other Search Techniques Proximity operators—e.g NEAR. A search for
“juveniles” NEAR “crime” would return sources with “juvenile” and “crime” usually within a specified range such as 10 words (not available for Google)
Trunication—e.g *. Search for a specific beginning or ending with all possible for the unspecified part. Search for “*hood” would get “parenthood” “neighborhood”, etc. This is not available in Google
Phrase search– “my search phrase”, available in Google and Teoma, etc.
Use – and + instead of NOT and AND. Available in Google
What This Means If you are looking for general information about a topic of
interest choose yahoo or askjeeves
If you have specific information and/or a possible topic with limited available information choose google
Practice with search engines, check their operation and rules to improve your search engine choice and limit extraneous information. You can check this list for possible search engines:
Search Engine List
Keep up with new developments.Http://www.searchenginewatch.com/
Learn more from an online tutorial on performing searches
http://www.sc.edu/beaufort/library/pages/bones/bones.shtml
Other Types of Search Engines 1Meta-Searches; these organize links received from searches by more then one
search engine. http://www.metacrawler.com/ http://www.ixquick.com/ http://www.dogpile.com/ http://www.clusty.com
Specialized Search Engines
http://newslink.org Newspaper Articles http://www.searchmil.com Military Information http://www.firstgov.gov/ USA Government Site http://www.switchboard.com Digital Phone Directory http://www.wikipedia.com Public Editable Encyclopedia http://www.clipart.com/ Images http://www.apple.com/itunes/ Music http://www.napster.com/ MPMusic3 Audio – now charges
Other Information Sources Specialized Information Searches
http://www.mayoclinic.com Medical advice http://www.fda.gov/cder/orange/default.htm FDA’s
Center for Drug Evaluation http://www.bizrate.com Store ratings and product prices. http://www.shopping.com Store ratings and product
prices http://froogle.google.com/ Search for a product
URL Uniform Resource Locator
Specifies where an identified resource is available and the mechanism for retrieving it
Examples:www.rcschool.net
Web extensions.com company .ac Higher ed outside of US
usually used with country code, example “ac.uk”
.sch school (used outside of US) .net network
.k12 most US school sites .mil US Military
.edu US higher ed .co Company (if paired with a country code, example “.co.uk, “the state of Colorado or the country Columbia)
.org organization .gov US government (add country code for outside US
.us American Web sites and is the newest extension
Conducting a Search Online Search for a list of academic institutions in
South AfricaGo to any browser and type host:ac.za
Search for US higher education websites that contain the word turtleGo to any web browser and type in “host:edu +
turtle” in the search box.
Websites Find the owner of a website by going to
www.easy whois.com and entering the URL of the site you would like to research.
Find out if a web site is someone’s personal website by looking for a tilde “~” or the “%” sign or a personal name “jdoe” or the word “user” after the domain name and the first forward slash “/”
Find out who is linked to your organization’s website by going to any browser and typing link:[your organization’s website]
Find the history of any given website by going to www.archive.org and entering in a website.
Blogs A weblog or blog (a derivative of “web” and “log”)
Essentially an online diary, where anyone with a basic knowledge of computers can post anything – random thoughts, photos, homework, and poetry, just to name a few – for the rest of the world to see.
Examples: Yellow Lane Politics 1 House of Blog Interactive Media Seminar
Questions