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Introduction to Computers → Memory This page is part of the Introduction to Computers project.

Contents 1 Memory 1.1 RAM 1.1.1 Primary storage 1.1.2 Random access memory 1.1.3 Volatile 1.1.4 Fast 1.2 ROM 1.3 CMOS

[edit] Memory

Primary storage, or memory, means the space on your hard drive that is briefly used for working space. This usually occurs in a chip. Memory consists of four types of memory chips RAM, ROM, CMOS and flash.

[edit] RAM

RAM stands for Random Access Memory and is a type of chip used in primary storage memory. It is also temporary storage, holding software instructions and short-term working memory for the processor. RAM can be increased in most computers by using the expandable memory slots. Ram video

[edit] Primary storage

Primary storage (RAM)is called 'primary' because it is the main memory that is accessible to the CPU. It is used to store data that is currently being used.Primary_storage

[edit] Random access memory

Random access memory or RAM is a form of data storage used in computers. Taken in the form of integrated circuits which represents primary or temporary storage, it allows data which is stored to be accessed in any order, which is why it's called random. Making it random instead of sequential greatly increases the speed the computer can operate since time is not wasted going to the place where needed data is stored (as in tape backups). Random_access_memory

[edit] Volatile

Volatile is a descriptive word for RAM which is short term memory; when the computer loses power the temporary storage will be lost . In order to prevent data from being lost, it must be saved to a hard disk [247].

[edit] Fast

RAM (in most cases)work faster than a hard drive, and some, faster than flash memory (which isn't volatile). This greater speed is why it's still used in computers today. Computers will run faster and more efficiently with more amounts of RAM. The suggested amount of RAM for current operating systems such as Windows Vista/xp and OSX 10.5 to run smoothly with the weight of shared graphics memory and programs is 1024 megabytes. Currently, RAM comes in 3 types: DDR1, DDR2, And DDR3. DDR1 and 2 are currently most used. DDR3 operates at a higher frequency and has 3 data transfer channels thus increasing bandwidth. Newly developed SSD hard disks currently are capable of meeting and exceeding the transfer rate of DDR and DDR2.

A 32bit operating system is only capable of utilizing 4gb of RAM. However 64bit is capable of supporting much more memory.

[edit] ROM

ROM refers to a read only memory chip that cannot be written on or erased by the computer user without special equipment. While using ROM contents are not lost when power to the computer is no longer available.

Since it does not need power, and cannot be rewritten the only things put on ROM are starting (booting) instructions.

[edit] CMOS

CMOS stands for Complementary metal–oxide–semiconductor. This is a technology used in chips and analog circuits. Cmos

Don't lose contents when turned off even if the content was not saved. Also keeps the time and date current even when the computer is turned off.