DEPT: SCIENCE
EDUCATION
FACULTY: EDUCATION
OPTION: CHEMISTRY EDUCATION
COURSE
TITLE: INTRODUCTION TO COMPUTER
COURSE
CODE: CSC 101
TOPIC:
WRITE AND DISCUSS ON THE DIFFERENT
TYPES OF COMPUTER
TYPES OF COMPUTER BASED ON CATEGORIES
a. Classical
(digital)
b. Non-classical
(analogue)
(a.) CLASSICAL
COMPUTER: Classical Computer is focused on what we will often call a
digital computer. It is the kind of computer that are all most familiar with.
It is the kind that you use for example a Mac or a Pc.
(b) NON-CLASSICAL
COMPUTER: it is focused on computer like the connectionist computer,
artificial neural network, analog computer and parallel distributed process of,
to name few.
Two of the properties that
distinguish non-classical computer form a digital computer involved the way
that information carried in the system. In a non-classical computer, at least
some of the information is carried in analog rather than digital and the
information is distributed throughout large section of the system rather than
localized in specific places.
1. ANALOG
COMPUTER: It represent numbers as physical magnitudes such as voltage,
resistance, temp, pressure e.t.c. In essence, they measure values of CONTINOUS
VARIABLES. It performs the calculations, which the operator manipulates through
the computer framework. Some of the computer are:
- potentiometers, -operational
amplifiers,
- integrators, -fixed-function
generation.
Examples
of analog computers that have been constructed or practically used.
- Nomogram, Astrolabe, - The slide
rule, mechanical integrator, - water integrator, Norden bomb sight and many
others.
2. DIGITAL COMPUTERS: It is used to
represent data using discret expressed in a numbering system.
3. Hybrid
Computers: These are special purpose computers that incorporate digital
computers into analog processing elements. That in essence means that they can
function both as a digital computer as well as an analog computer.
DIGITAL COMPUTER CLASSIFICATION BASED ON
SIZE AND SUPER COMPUTER AND MAINFRAME
(2a) Super
computer is a broad term for one of
the fastest computers currently available. Super computers are very expensive
and are employed for specialized applications that require immense amounts of
mathematical calculations (number crunching) for example, weather forecasting
requires or supercomputer. Other uses of supercomputers scientific simulations,
(animated) graphics, fluid dynamic calculations, nuclear energy research,
electronic design, and analysis of geological data (e.g in petrochemical
prospecting)-perhaps the best known super computer manufacturer is Cray Research.
2. Mainframe Computer was a term originally reggering to the cabinet
containing the contract processor unit or
“main frame”. Of a room filling stone Age batch machine.
After the emergence of smaller
“minicomputer” designs in the early 1970’s the traditional big iron mechanics
were described as “mainframe computer” and eventually just as mainframes.
Nowadays, a mainframe is a very
large and expensive computer capable of supporting hundreds, or even thousands,
of users simultaneously. The Chief difference between a super computer and a
mainframe is that a super computer channels all its power into executing a few
programmes as faster possible, where as a mainframe uses its power to execute
many programs concurrently.
In some ways, mainframes are more
powerful than super computers because they support more simultaneous
programmes. But super computers can execute a single program faster than a
mainframe. The distinction between small mainframes and minicomputers is vague,
depending really on how the manufacturer wants to market its machines.
3. Mini computer: It is a midsize computer in the past decade, the
distinction between large minicomputer and small mainframes has blurred,
however, as has the distinction between small minicomputers and workstations.
But in general, minicomputers is a multiprocessing system capable of supporting
form up to 200 users simultaneously.
4. Workstation: It is a type
of computer used for engineering applications (CAD/CAM), desktop publishing,
software developments and other types of applications that require a moderate
amount of computing powers and relatively high quality graphics capabilities.
Workstations generally come with a large, high-resolution graphics screen, at
large amount of “RAM”, built in-network support, and a graphical user
interface. Most workstations also have a mass storage device such as a disk
drive, but special type of workstation called a diskless workstation) comes
without a disk drive. The most common separating systems for workstations are UNIX
and windows NT like personal computers. However, workstation are typically
linked together to form a local-area network, although they can also be used as
stand-alone systems. But is networking, workstation refers to any computer
connected to a local area network. It could be a workstation or a personal
computer.
5. Personal computer: It can be
defined as a small, relatively inexpensive computer designed for an individual
uses. In price, personal computers range anywhere form a few hundred pounds to
over five thousand pounds. All are based on the micro processor technology that
enables manufacture to put an entire CPU on are chip. Businesses use personal
computers for world processing, accounting, desktop publishing and for running
spreadsheet and data basic management applications. At home, the most popular
use for personal computers is for playing games and recently for surfing the
internet.
Personal computer first appeared in
the later 1970s. one of the first and most popular personal computers was the
Apple II, introduced in 1977 by apple computer, during the later 1970s and
early 1980s, new models and computing operating systems seemed to appear daily.
Then in 1981, IBM entered the fray with its first personal computer, known as
the IBM PC. The IBM PC quickly become the personal computer of choice and most
other personal computer manufacturers fell by the wayside. P.C is sort for
personal computer or IBM on slaught was apple computer which remains a major
player in the personals” computer marketplace. Other companies adjusted to IBM
and dominar a by building IBM dones, computers that were internally almost the
same a the IMB Pc, but that coatless.
In recent years, the term PC has
became more and more difficult to p in down. In general, though, it applies to
any personal computer base on an intel microprocessor, or on an
Intel-compatible micro process.
Today, the world of personal
computers is basically divided between Apple Macintoshes and PCS. The principal
statistics of personal computers are that they are single-user systems and are
based on microprocessors.
CLASSIFICATION OF PERSONAL COMPUTERS: It can be classified by size and chassis/case. Then
are two basic flavors of chassis designs-desktop model & tower models-but
there are many variations on these two basic types. Hen come the “portable
computer” that are computers small enough to carry. Portable computers include
notebook and sub notebook computers hand-held computers, maintops and most popular
computers used today.
CLASSIFICATION OF PERSONAL COMPUTER
* Tower Model: It is a type
of computer in which the power supply, mother board and mass storage devices
are stacked on top of each other in a cabinet. This is in contrast to desktop
models, in which these compact box. The main advantage of tower models is that
there are fewer space constraints which make installation of additional storage
devices easier.
* Desktop: This is a type of computer
designed to fit comfortably or top of a desk, typically with the monitor
sitting on top of the computer.
Desktop model computers are broad and low, whereas tower model computers are
narrow and tall, because of their shape, desktop model computers are generally
limited to three internal mass storage devices. Desktop model designed to be
very small are sometime referred to as slim line models.
Classes of portable computer
1.
Notebook computer: It is an extremely lightweight personal computer. Notebook computers
typically weightless than 6 pounds and are small enough to fit easily in a
brief case Aside form size, the principal difference between a notebook
computer and a personal computer is the
display screen. Notebook computers use a variety of techniques, known as flat
panel technologies, to produce a light weight and non-bulky display screen. The
quality of notebook display screens varies considerably. In terms of computing
powers” modern notebook computers” are nearly equivalent to “personal computers”
they have the same CPU, memory capacity and disk drives. However, all this
power in a small package is expensive. Note book computer cost about twice as
much as equivalent regular-sized computers. Notebook computers come with
battery packs that enable you to run them without plugging them in. however,
the batteries need to recharged every few hours.
2. Laptop
computers: It is a small, portable
computer-small enough that it can sit on your lap. Nowadays, laptop computers
are more frequently called notebook computers. Laptop computers are lightweight
and portable. A person sings a laptop should be able to run the same software
on the laptop as well as on larger desktop computers. Desktop computer of
operating system as desktop. Modern laptops can have floppy drives, CD-Rom
drives and CD rewriters and even DVD drives. They often have a full sized; or
near full size, keyboards and a mouse or a touch-sensitive mouse pad. The
screen is usually a large liquid crystal display (LCD). Laptops are usually
much more expensive than desktop computers. They have expressive battery packs
that have to power the hard disk, CD drives and LCD screen. The batteries
generally don’t last as long as those in a packet computer and may need
recharging more than once a day.
The main advantage of a laptop is
that the person using it can have all the programe and data from their desktop
computer on a portable computer.
3. Sub
Notebook Computer: It is a
portable computer that is slightly lighter and smaller than a full-sized note
book computer. Typically, sub note book computer have or smaller keyboard and
screen, but are otherwise equivalent to notebook computer.
4. Hand
held computer: This is a
portable computer that is small enough to be held in one’s hand. Although
extremely convenient to carry, hand held computer have not replaced not a book
computers because of their small keyboards and screens. The most popular
band-held computers are those that are specifically designed to provide PIM
(personal information manager) functions, such as a calendar of address book in
some manufacturers are typing to solve the small keyboard problem by replacing
the keyboard within electronic pen. However, these per-based devices rely on
handwriting recognition technologies, which are still in their infancy. Hand
held computer are also called PDAs, palmtops and pocket computers.
5 Palmtop: It is a small computer that literally fits in your
palm. Compared to full-size computers, palmtops are severely limited, but they
are practical for certain functions such as phone books and calendars. Palmtops
that use a pen rather than a keyboard for input are often called hand-held
computers on PDAs. Because of their small size, most palmtop computers do not
include disk drives. However, many contain PCM CIA slots in which you can
insert disk drives, moderns, memory and other disk drives, moderns, memory and
other devices palmtops are also called PDA, hand-held computers and pocket
computers.
6. PDA:
these are short for personal digital assistant, a hand held device that
combines computing, telephone fax and networking features. A typical PDA can
function as a cellular phone fax sender,
and personal organizer. Unlike portable computers most PDAs are pen-based,
using a styles rather than a keyboard for input. This means that they also
incorporate handwriting recognition features some PDAs can also react to voice
input by using voice recognition technologies by Apple computer, which
introduced the Newton Message pad in 1993. shortly thereafter, several other
manufactures offered similar products. To date, PDAS have had only modest
success in the market place, due to their high price tags and limited
applications. However, many experts believe that PDAS will eventually become
common gadgets.
PDAS
are also called palmtops, handheld computers, and pocket computers.