Learn Computer

  Introduction:                           Computer memory is one of the important and compulsory components of every computer. It is the electronic holding place for instructions and data accessed by computer . Computer memory is used to store data or programs on a temporary or permanent basis for use in a computer . Computer memory is divided into two main types: Primary or Main or Internal Memory Secondary or Auxiliary or Backing Storage Memory Primary or Main memory holds instructions and data when a programs executed, while secondary memory holds data and programs not currently in use and provides long-term storage.

 Super computers:                                                                 Super Computer are the most powerful and the most expensive computers designed for scientific, engineering, and business applications. These Computers can process billions to trillions of instructions per second. The usage includes world-wide weather forecasting, weapon research, stock analysis, automobile designing, special effects for movies and used for applications requiring complex mathematical calculations. Supercomputers possess extremely high computing speed, higher capacity for storage, faster primary memory and faster secondary storage as compared to other types of computers. IBM's supercomputer, sequoia, can perform around 16 thousand trillion instructions per second. These computers are used for research and exploration purposes, like NASA uses supercomputers for launching space shuttles, controlling them and for space exploration purpose.

 Mainframe Computers:                                                                                       Mainframe computers are the second powerful and expensive computer than supercomputers . Mainframes are used mainly by large organization for critical applications , typically bulk data processing such as census, industry and consumer statistics, enterprise resource planning,  and financial transaction processing. These computers have powerful processors and large memories to process large amounts of data at very high speed, such as billions of industries per second (BIPS) .  These computers support many terminals at the same time.                                                                                       These are widely used as super-servers for large client/server networks and for high volume websites. Mainly these are used by airline companies, government departments , banks and insurance companies. Automated Teller Machine (ATM) is an example of an mainframe

 DRAM (Dynamic Random Access Memory):                                                                                                                                                            DRAM is a type of semiconductor memory where the word "Dynamic" indicates that it needs to be periodically refreshed to retain its data. it stores each bit of data in a separate capacitor within an integrated circuit. The capacitor can be either charged or discharged' these two states are taken to represent the two values of a bit, conventionally called 0 and 1. in personal computers DRAMs are used as internal memory because of their simple structure that allows high storage and low cost as compared to SRAM   .   Types of DRAM:                                             There are two types of DRAM  SDRAM DDR SDRAM    SDRAM:                                        SDRAM stands for Synchronous Dynamic Random Access Memory. SDRAM is a high speed semiconductor memory. it is an im

 SRAM :-                               SRAM is a type of semiconductor memory where the word "Static" indicates  that it does not need to be periodically refreshed to retain its data. SRAM is more expensive, but faster and significantly less power hungry than DRAM . due to a more complex internal structure,   SRAM is less dense than DRAM and is therefore not used for high-capacity, low-cost applications such as the main memory in personal computers. Static RAM is mainly used to make the CPU's cache.

  There are two main  types of RAM : Dynamic  RAM  (DRAM) and Static  RAM  (SRAM). DRAM (pronounced DEE- RAM ), is widely used as a computer's main memory. ... SRAM (pronounced ES- RAM ) is made up of four to six transistors.