Urvashi Sahu

                                                                           computer   A   computer   is a   programmable   device that stores, retrieves, and processes   data . The term "computer" was originally given to humans ( human computers ) who performed numerical calculations using mechanical calculators, such as the   abacus   and   slide rule . The term was later given to a mechanical device as they began replacing the human computers. Today's computers are electronic devices that accept data ( input ),   process   that data, produce   output , and store ( storage ) the results.

Types of Computer Depending upon the internal structure and subsequent features and applicability, computer system is categorized as follows − (I) Mainframe Computer It is high capacity and costly computer. It is largely used by big organizations where many people can use it simultaneously. (II) Super Computer This category of computer is the fastest and also very expensive. A typical supercomputer can solve up to ten trillion individual calculations per second. (III) Workstation Computer The computer of this category is a high-end and expensive one. It is exclusively made for complex work purpose. (IV) Personal Computer (PC) It is a low capacity computer developed for single users. (V) Apple Macintosh (Mac) It is a sort of personal computer manufactured by Apple company. (VI) Laptop computer (notebook) It is a handy computer that can be easily carried anywhere. (VII) Tablet and Smartphone Modern technology has advanced further. It has helped develop computers that are pocket-friendly.