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Computer Appreciation
A computer is an electronic device that accepts data as input, processes it, and gives the required information as output. From the definition, the four components, peripherals, devices or accessories of a computer can be identified. They are input, processor, memory and output unit.
In our world today, computers have, in many ways, affected our lives. Computer has made life much easier in education, banking, journalism, accounting, telecommunications etc.
BRIEF HISTORY OF COMPUTERS
Computers were first made in the 20th century. The history of the modern computers is classified into four generations.
- First generation (1945-1955): it is characterized by the vacuum tube (thermionic valve) as its major functional electronic component.
- Second generation (1955-early1960s): characterized by the transistor which replaced the vacuum tubes as they were faster, smaller and emitted less heat.
- Third generation (19560s-1970s): was a major breakthrough in computing research with the advent of the IC (integrated Circuit) where hundreds of transistors could be integrated into a tiny silicon chip.
- Fourth generation: (1970s-till date): was a further development on the IC with a very large scale integration of thousands of transistors on a single chip. (The Personal Computer is a fourth generation computer).
Types of computers
Computers today are categorized based on size, cost and performance.
Supercomputers: These are the largest computers in terms of size, memory, data processing capability, speed as well as price. Scientists in weather forecasting, oil exploration, etc use super computers to make complex calculations.
Mainframe computers: Mainframe computers are the next largest, although most mainframes are a group of computers working together as a family rather than a single computer. The memory capacity is very high as well as processing capacity and capability. Large organizations like airports, power stations, population commission make use of mainframe computers.
Mini computers: They are the third largest. Minicomputers were developed for handling specialized tasks. They are special purpose computers that are not for general application.
Micro-computers: they are designed for personal use at home or in the office. It is often referred to as a PC (personal Computer). Examples are desktops, lap-tops/notebooks, palm-tops, Ipad, Android, organizers and calculator.
Uses of computer.
- To do word processing
- To do data processing which involves: calculating, sorting, classifying, summarizing.
- To provide information needed for decision making
- To store information.
- In banks, it is used to keep record of customer accounts and for dispensing money.
- To do weather forecasting etc
EVALUATION
- Define the computer
- State the four components of the computer.
SUB-TOPIC 2: INTERNET AND E-MAIL
Internet
The internet is a networking infrastructure that connects millions of computers and computer network all over the world, thereby forming a network through which any computer can communicate with any other computer that is connected to the internet. Internet is a global network of computer which communicates, using a common language. It is similar to the international telephone system, except that no one owns or controls the network. Information can be retrieve from millions of sources, e. g. schools, governments. The purpose of the internet is to share information either by sending or receiving of particular information. The internet can only be accessed through a computer connected to the internet or by means of a modem linked to a telephone line (Mtn, Glo and Etisalat modems) or through a satellite network(VSAT).
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