Computer is an electronic device that can process data at an amazingly fast speed and produce accurate results. Besides numerical data, it can also process other types of data such as alphabet and alphanumeric data. It also has the ability to store huge amount of data.
Computer is divided into two categories: Hardware and software.
Hardware the physical or tangible components forming a computer are called hardware includes not only the computer but also the cables, connectors, power supply units and peripheral devices such as, the keyboard, mouse, audio speakers, printers, etc.
Software refers to the programs that instruct the computer what to do. The term software refers to the non-physical elements of a computer system.
The capabilities the capabilities of computer are speed, repetitions, accuracy logical operation, store and recall information self-checking, and self-operating. While its limitations are that it cannot generate information on its own, it cannot correct wrong instructions. It cannot come up with an original decision.
History & generations today computers do much more than simply compute numbers. But when did all this technology come from and where is it heading? To understand this, it is important to understand their evolution. Name of early computing machines are abacus, Napier’s Bones, Slick Rule, Pascaline Engine, Babbage’s Analytical Engine, and Hollerith’s Tabulating machine, these innovations were developed in a period termed as Dark age and Middle age of the computers. There are many other scientists and innovations but these are the development that are milestones in the development stage of computer.
After dark and Middle ages, the computer technology and ideology improved and the period was termed as Modern age of computer. The computers in Modern age are categorized in live generations: each generation of computer is characterized by a major technological development that fundamentally changed the way computers operate, resulting in increasingly smaller, cheaper, and more powerful and efficient and reliable devices.
The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. Transistors replaced vacuum tubes in the second generation of computers. The development, of the integrated circuit (IC) was the hallmark of the third generation of computers; the microprocessors brought the fourth generation of computers, as thousands of integrated circuits were built into a single silicon chip. Fifth generation computing devices are based on artificial intelligence. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.
Computers are classified according to purpose, type of data handled, and capacity.
Purpose General, purpose computers are designed to handle a variety of different problems and to meet different needs. While special purpose computers are designed to handle a specific problem or to perform a specific task.
Type of data handled analog computers use analog methods to process data. An analog computer operates with numbers represented by directly measurable quantities, which vary continuously. Digital computers are computers that specialize in counting. Unlike the analog computer, which receives data in a continuous form, the digital computer handles values that are discrete in nature. Hybrid computer is combination of analog and digital computer systems.
Capacity super computers are the largest and fastest machines today where numerical computations are carried out at speeds of up to 50 million operations per second. Mainframe is made to model large dynamic computing needs of a big organization that serves hundreds of terminals all at the same time. These computers are the ultimate in sophistication, flexibility and speed. Mini-computers are increasingly powerful and do almost anything that large computers do, only more slowly and at much lower cost than mainframes. Microcomputers are computers that are powered by microprocessors.
Programming language a program is a set of step-by-step instruction that directs the computer to do the tasks you want it to do and produces the results you want. There are many languages that are categorized as under.
Machine language (Low-level language): Every creation of this universe has its own language. Likewise, computers, has language that is called machine language for instructing computer to perform specific task. It is language of Os and I s.
Assembly language Assembly language is the next level of programming language. Each computer has its own unique assembly language. In assembly language, the statements are written in symbolic codes (termed as mnemonics).
High level language high level language are closer tom human language than low-level languages, and include statements like GOTO and print which are regular words.
Concept of source and object program (Code): a program written in any language except the machine language is called source program. Source program must be converted to machine language code called object program in order to execute. Language translators are used to serve this purpose i.e. conversion of source program into object program.
Language translator language translators are the programs that are used to convert source program to object program.
Assembler is a program that converts an assembly language program into machine language. Compiler is similar to assembler in way that it translates the high, level language program into machine language. Interpreter is also used to translate high-level program into machine language but it translates the program every time you will execute it.