Introduction to ComputerIntroduction to Computer

ADEEL ANJUMADEEL ANJUM

Computers for Individual UsersComputers for Individual Users

Most computers are meant to be used by only Most computers are meant to be used by only one person at a timeone person at a time

Such computers are often shared by several Such computers are often shared by several people, but only one user can work with the people, but only one user can work with the machine at any given momentmachine at any given moment

Such type of computers are examples of Personal Such type of computers are examples of Personal Computers (PCs)Computers (PCs)

Personal Computers are also called Personal Computers are also called microcomputers, because they are among the microcomputers, because they are among the smallest computers created for people to usesmallest computers created for people to use

Computers for Individual Users (Cont..)Computers for Individual Users (Cont..)

Microcomputers are the smallest and less expensive of Microcomputers are the smallest and less expensive of all the computersall the computers

The capability is limited as compare to other The capability is limited as compare to other computerscomputers

The six primary types of computers in this category The six primary types of computers in this category are:are:

>>>> Desktop ComputersDesktop Computers

>>>> WorkstationsWorkstations

>>>> Notebook ComputersNotebook Computers

>>>> Tablet ComputersTablet Computers

>>>> Handheld ComputersHandheld Computers

>>>> Smart PhonesSmart Phones

Desktop ComputersDesktop Computers The most common type of personal computer is the desktop computerThe most common type of personal computer is the desktop computer

A PC that is designed to sit on a desk or tableA PC that is designed to sit on a desk or table

These computer not only enable people to do their jobs with greater These computer not only enable people to do their jobs with greater ease and efficiency, but they can be used to communicate, produce ease and efficiency, but they can be used to communicate, produce music, edit photographs and videos, play sophisticated games, and music, edit photographs and videos, play sophisticated games, and much moremuch more

As its name implies, a desktop computer is a full-size computer that is As its name implies, a desktop computer is a full-size computer that is too big to be carried aroundtoo big to be carried around

The main component of a desktop PC is the The main component of a desktop PC is the system unit, system unit, which is the which is the case that houses the computer’s critical parts, such as its processing case that houses the computer’s critical parts, such as its processing and storage devicesand storage devices

Desktop ComputersDesktop Computers

There are two common designs for desktop There are two common designs for desktop computerscomputers

The more traditional desktop model features a The more traditional desktop model features a horizontally oriented system unit, which usually horizontally oriented system unit, which usually lies flat on the top of the user’s desklies flat on the top of the user’s desk

Many users place their monitor on top of the Many users place their monitor on top of the system unitsystem unit

Desktop ComputersDesktop Computers

Vertically oriented tower models have become the Vertically oriented tower models have become the more popular style of desktop systemmore popular style of desktop system

The design allows the user to place the system unit The design allows the user to place the system unit next to or under the desknext to or under the desk

WorkstationsWorkstations A workstation is a specialized, single user computer that typically has A workstation is a specialized, single user computer that typically has

more power and features than a standard desktop PCmore power and features than a standard desktop PC

These machines are popular among scientists, engineers, and animators These machines are popular among scientists, engineers, and animators who need a system with greater-than average speed and the power to who need a system with greater-than average speed and the power to perform sophisticated tasksperform sophisticated tasks

Workstations often haveWorkstations often have

large, high resolution large, high resolution

monitors and accelerated monitors and accelerated

graphics handling graphics handling

capabilitiescapabilities

Notebook ComputersNotebook Computers Notebook computers, as their name implies, approximate the shape of Notebook computers, as their name implies, approximate the shape of

an 8.5-by-11 inch notebook and easily fit inside a briefcasean 8.5-by-11 inch notebook and easily fit inside a briefcase

Because people frequently set these devices on their lap, they are also Because people frequently set these devices on their lap, they are also called laptop computerscalled laptop computers

Notebooks are fully Notebooks are fully

functional microcomputers functional microcomputers

and they are portableand they are portable

Tablet PCsTablet PCs The tablet PC is the newest development in portable, full-featured The tablet PC is the newest development in portable, full-featured

computerscomputers

Tablet PCs offer all the functionality of a notebook PC, but they are Tablet PCs offer all the functionality of a notebook PC, but they are lighter and can accept input from a special pen-called a lighter and can accept input from a special pen-called a stylusstylus or a or a digital pen-digital pen-that is used to tap or write directly on the screenthat is used to tap or write directly on the screen

Many Tablet PCs alsoMany Tablet PCs also

have a built-in microphonehave a built-in microphone

and special software thatand special software that

accepts input from accepts input from

the user’s voicethe user’s voice

Handheld PCsHandheld PCs Handheld personal computers are computing devices small enough to Handheld personal computers are computing devices small enough to

fit in your handfit in your hand

A popular type of handheld computer is the Personal Digital Assistant A popular type of handheld computer is the Personal Digital Assistant (PDA)(PDA)

A PDA is no larger than a small appointment book and is normally A PDA is no larger than a small appointment book and is normally used for special applications, such as taking notes, displaying used for special applications, such as taking notes, displaying telephone numbers and addressestelephone numbers and addresses

Many PDAs let the user access Many PDAs let the user access

the Internet through a wireless the Internet through a wireless

connection, and several models connection, and several models

offer features such as cellular offer features such as cellular

telephone, and cameras etc.telephone, and cameras etc.

Smart PhonesSmart Phones

Some phones offer advanced features not Some phones offer advanced features not typically found in cellular phones, they are typically found in cellular phones, they are sometimes called smart phonessometimes called smart phones

These features can include Web and e-mail These features can include Web and e-mail access, special software such as personal access, special software such as personal organizers, or special hardware such as digital organizers, or special hardware such as digital camerascameras

Computers for OrganizationsComputers for Organizations

Some computers handle the needs of many users at the Some computers handle the needs of many users at the same timesame time

These powerful systems are most often used by These powerful systems are most often used by organizations, such as businesses or schools, and are organizations, such as businesses or schools, and are commonly found at the heart of the organization’s commonly found at the heart of the organization’s networknetwork

The largest organizational computers support thousands The largest organizational computers support thousands of individual users at the same time, from thousands of of individual users at the same time, from thousands of miles awaymiles away

These computer are:These computer are:>>>> Network ServersNetwork Servers

>>>> Mainframe ComputersMainframe Computers

>>>> MinicomputersMinicomputers

>>>> SupercomputersSupercomputers

Network ServersNetwork Servers

Most organizations’ networks are based on Most organizations’ networks are based on personal computerspersonal computers

Individual users have their own desktop Individual users have their own desktop computers, which are connected to one or more computers, which are connected to one or more centralized computers, called centralized computers, called network serversnetwork servers

A network server is usually a powerful personal A network server is usually a powerful personal computer with special software and equipment computer with special software and equipment that enable it to function as the primary computer that enable it to function as the primary computer in the networkin the network

Mainframe ComputersMainframe Computers Mainframe computers are large in size, expensive and Mainframe computers are large in size, expensive and

more powerful systemmore powerful system

The largest mainframes can handle the processing needs The largest mainframes can handle the processing needs of thousands of users at any given momentof thousands of users at any given moment

Mainframe computers are used in large organizations, Mainframe computers are used in large organizations, such as insurance companies, banks, universities, and such as insurance companies, banks, universities, and international markets, where many people need to use the international markets, where many people need to use the same datasame data

In a traditional mainframe environment, each user In a traditional mainframe environment, each user accesses the mainframe’s resources through a device accesses the mainframe’s resources through a device called a terminalcalled a terminal

Examples of mainframe computers are IBM-4381, ICL-Examples of mainframe computers are IBM-4381, ICL-2900, and NEC 610 etc.2900, and NEC 610 etc.

Mainframe ComputersMainframe Computers

MinicomputersMinicomputers First released in the 1960s, minicomputers got their First released in the 1960s, minicomputers got their

name because of their small size compared to other name because of their small size compared to other computers of the daycomputers of the day

The capabilities of a minicomputer are somewhere The capabilities of a minicomputer are somewhere between those of mainframes and personal computers. between those of mainframes and personal computers. For this reason, minicomputers are often called midrange For this reason, minicomputers are often called midrange computerscomputers

Powerful Minicomputers can serve the input and output Powerful Minicomputers can serve the input and output needs of hundreds of users at a timeneeds of hundreds of users at a time

Users can access a central minicomputer through a Users can access a central minicomputer through a terminal or a standard PCterminal or a standard PC

Examples of mini computers are PRIME-9755 and IBM Examples of mini computers are PRIME-9755 and IBM System 36 etc.System 36 etc.

Mini ComputerMini Computer

SupercomputersSupercomputers Supercomputers are the most powerful computers made, and Supercomputers are the most powerful computers made, and

physically they are some of the largestphysically they are some of the largest

These systems can process huge amount of data, and the fastest These systems can process huge amount of data, and the fastest supercomputers can perform more than one trillion calculations per supercomputers can perform more than one trillion calculations per secondsecond

Some supercomputers can house thousands of processorsSome supercomputers can house thousands of processors

Supercomputers are ideal for handling large and highly complex Supercomputers are ideal for handling large and highly complex problems that require extreme calculating powerproblems that require extreme calculating power

Supercomputers are used for forecasting the weather, oil exploration, Supercomputers are used for forecasting the weather, oil exploration, film imagery, and modeling complex processes like nuclear fissionfilm imagery, and modeling complex processes like nuclear fission

Examples of supercomputers are CRAY-1 and CYBER-205Examples of supercomputers are CRAY-1 and CYBER-205

Super ComputerSuper Computer

1.1. General Purpose ComputerGeneral Purpose Computer

• Most computers in use today are general purpose Most computers in use today are general purpose computerscomputers

• These are built for a great variety of processing These are built for a great variety of processing jobsjobs

1.1. Special Purpose ComputerSpecial Purpose Computer

• A special computer as the name implies is A special computer as the name implies is designed to perform a specific operationdesigned to perform a specific operation

• Special purpose computers are also known as Special purpose computers are also known as dedicated computersdedicated computers

• Such computers would be useful in games, Such computers would be useful in games, control traffic lights, weather prediction etc.control traffic lights, weather prediction etc.

Types of Computer (w.r.t. purpose)