What Is Main Memory?

Main memory is volatile which means that it is lost when the system is shut off. It provides direct access to data stored in it. The database does not usually fit in main memory, which is limited in size and must hold not only data but systems programs and applications programs. However, any data that is to be processed must first be brought into a portion of main memory called the buffer. When a record is requested, the system checks to see if it is already in buffer. If so, the system simply passes the address in the buffer to the requesting process. If not, the system finds the location on disk where the record is stored and directs the reading of the record into the buffer.  Since accessing records in the buffer is many times faster than accessing those on disk, records that are used most frequently are sometimes kept in the buffer whenever the database is in use. Main memory is erasable i.e. its lost it data if there is some kind of abnormal termination like system shut off, application terminates etc.

It is an array of words or bytes. It has different sizes such as 64 MB, 256 MB, 512 MB, etc. It is used for loading and running programs and operating system. Whenever we want to execute a program on computer then that program comes in main memory from secondary memory (Hard Disk) and then that program execute. It means that main memory is an essential part of a computer and you cannot run a computer without it and computer programs must be in main memory to be executed. Main memory is different from secondary memory as main memory is used for running a program while secondary memory is used for storing data.

Main memory is the only large storage area that the processor can access directly. It is a volatile storage device. It means that it loses all its data (contents) when computer power is turned off and due to this reason secondary storage device is used. But it doesn't means that this is the only purpose as secondary storage devices are used because we want to place some data on permanent basis in computer and secondary storage devices cannot take place of main memory.

Main memory means,  term for main memory is RAM(Random Access Memory). The amount of main memory on a computer is very crucial because it determines how many programs can be executed or run at a one time and how much data can be store in computer. It can increase the computer performance.

Yes...main memory means some times we call it primary memory(RAM) or it is our working area on the computer. The more you upgrade your memory capacity you can perform a lot of tasks at a time so the least that i tell you it is better to upgrade your PC RAM my friend.

Memory is a form of rectangle inside the system unit