Types of Computers

·         Analog Computer

·        Digital Computer

·        Hybrid computer

Analog Computer

n  Analog Computers handle or process information which is of a physical nature, as for example, temperature, pressure etc.

n  Images of Analog Computers

Digital Computer

n  Digital computers process information which is essentially in a binary or two- state form, namely zero and one.

n  When talking about computers, we mostly refer to the digital type of electronic machines. These are based on the measuring of analog or equivalent physical value.

Microcomputer

n  Can be classified into:

n  Desktop PCs                           

n  sits on desks, rarely moved, large and bulky.

n  Memory capacity, graphics capacity and software availability vary from one computer to another Used both for business and home applications

Microcomputer

n  Portable PCs

n  Can be moved easily from place to place

n  Weight may varies

n  Small PCs are popular known as laptop

n  Widely used by students, scientist, reporters, etc

                                                Microcomputer                                            


n  Advantages

n  Small size

n  Low cost

n  Portability

n  Low Computing Power

n  Commonly used for personal applications

n  Disadvantages

n  Low processing speed

Uses of Microcomputer

n  Word Processing

n  Home entertainment

n  Home banking

n  Printing

n  Surfing the internet

Minicomputer

n  Medium sized computer

n  Also called the minis

n  e.g., IBM36, HP9000, etc

n  Computing power lies between microcomputer and mainframe computer

Minicomputer

n  Characteristics

n  Bigger size than PCs

n  Expensive than PCs

n  Multi-User

n  Difficult to use

n  More computing power than PCs

n  Used by medium sized business organizations, colleges, libraries and banks.

Uses of Minicomputer

n  Control of Automated Teller Machine (ATMs)

n  Payroll

n  Hospital patients’ registration

n  Inventory Control for supermarket

n  Insurance claims processing

n  Small bank accounting and customer details tracking

                                                Minicomputer                            


n  Advantage

n  Cater to multiple users

n  Lower costs than mainframes

n  Disadvantage

n  Large

n  Bulky

Mainframe

n  Known as enterprise servers

n  Occupies entire rooms or floors

n  Used for centralized computing

n  Serve distributed users and small servers in a computing network

Main Frame

n  Large, fast and expensive computer

n  Cost millions of dollars

n  e.g., IBM3091, ICL39, etc

n  Characteristics:

n  Bigger in size than minicomputers

n  Very expensive

n  Support a few hundred users simultaneously (Multi-Users)

n  Difficult to use

n  More computing power than minicomputers

n  Have to be kept in a special air-conditioned room

n  Used in big business organizations and government departments

Areas where mainframes are used

n  Airline reservation

n  Big banks with hundreds of branches located all over the world

n  Big universities with thousands of enrolments

n  Natural gas and oil exploration companies

n  Space Vehicle control

n  Weather forecasting

n  Animated Cartoon

n  Some mainframes are designed to be extremely fast and called super computers. It is used for space launching, monitoring and controlling.

                                                Mainframe


n  Advantage

n  Supports many users and instructions

n  Large memory

n  Disadvantage

n  Huge size

n  Expensive

 

Supercomputer

n  Fastest and expensive

n  Used by applications for molecular chemistry, nuclear research, weather reports,  and advanced physics

n  Consists of several computers that work in parallel as a single system

                                                                    Super Computer


n  Advantage

n  Speed

n  Disadvantage

n  Generate a large amount of heat during operation