Types of Main Memory
1- Read-write or random access memory( RAM)
It has a variable content , also it is generally used to store the variable data. RAM can also be used to store frequently changed programs and other information. The term “random” means that any memory location can be accessed in the same amount of time, regardless of its position in the memory.
RAM allows the computer to store information quickly for later reference:
1- The active part of the operating system, the fundamental program that control the operation of the computer.
2- The application program being executed (for example a letter being written with the word processing program).
3- A representation of the data being presented on the video display
In RAM, the stored information will be lost when computer power supply is removed (even a short interruption). That is RAM, is volatile memory. Some form of RAM, called flash memory, retain their electrical charges when a computer is turned off When program instruction, reads the data in memory address, it gets a copy of the data. This is called a nondestructive read, because the contents of the memory address are not changed. Sending data to a RAM memory address is called a destructive write, because the new data erases whatever was there before.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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