About Computer Generations
Computer is an electronic device used to accept the data in the form of digitalized (binary 0 and 1) to perform some task based on the sequence of instructions program. Five generations of computers,
First generations of computers (1940-56) operated in vacuum tubes. Computers use the vacuum tubes for circuitry and magnetic drums for memory. The drum rotates at a speed of 3000 rpm. This computer is very expensive to operate and it wants more electric power and it produces a lot of heat. First generations of computer understood machine level language, lowest level programming language to perform the operation. Input of the system is punched cards and paper tape and the output was displayed only on printers.
Disadvantage,
It requires more space
Very expensive to operate
It needs more power
Second generation computer (1956-63) transistors replace the vacuum tubes. Transistors are devices that consist of semiconductor material that amplify the signal. Transistors eliminate the disadvantage of vacuum tubes (i.e.) large, heat, energy. The transistors was a superior to the vacuum tubes, allow computers become small, faster, cheaper, reliable, efficient. This computer understood only assembly or symbolic high level language. The high level language such as COBOL, FORTRAN.
Advantage
Small
Faster and reliable
Cheap and efficient
The third generation of computer (1964-71) integrated circuits. In this computer instead of punch cards, printouts, user interact through keyboards, monitors and infrared with operating system, which allow the system run a many application at a time. Computers chips for both CPU and memory are composed of semiconductor materials.
Advantage
It is very speed
Small and reliable
The fourth generation of computer (1971-at present) microprocessor. Microprocessor consists of thousands of integrated circuits. Intel 4004 chip developed in 1971 located all the components of computers from the CPU and memory. There are two components in CPU that are arithmetic logic unit, control unit. This small computer became more powerful and also having GUI, mouse and handheld devices.
Advantage
Small size
More reliable
Easy to use
The fifth generation of computer (Present and Beyond) artificial intelligence. All the devices based on artificial intelligence, are still in development, through some applications, such as voice recognition, that are being used today. Parallel processing, super conductor are used to make the artificial intelligence. The goal of fifth generation computers is to develop that respond to natural language input and capable of learning and self organisation.
Advantage
Easy to access
Easy to use
Small size