# Introduction to Computers/Memory

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Primary storage, or memory, refers to the space on your hard drive that is briefly used for working space. This usually is stored in a chip. Memory consists of four types of memory chips: RAM, ROM, CMOS and flash. RAM stand for random access memory and ROM stand for read only memory. These are also called primary memory of a computer.

## RAM

RAM stands for Random Access Memory. It is memory that needs to be used or accessed quickly by the CPU. It is stored and is a type of chip which is specifically designed for it. RAM can also be referred to as the "primary storage" of a computer, because it is the main memory accessible to the CPU. It holds software instructions and short-term working memory for the processor so that the processor can easily access this data in one place. RAM can be increased in most computers by using the expandable memory slots. More RAM allows computers to operate more efficiently.
Primary_storage
RAM is taken in the form of integrated circuits which represent primary or temporary storage. These circuits allow stored data 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

### Volatile

Volatile is a descriptive word for RAM; it means that when the computer loses power, the RAM will be lost. In order to prevent data from being lost, it must be saved to a hard disk or permanent storage area called ROM (Read Only Memory)[247].

### Fast

RAM, in most cases, works 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 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 (1GB). Currently, RAM comes in 4 types: DDR1, DDR2, DDR3, DDR4 and DDR5 available since 2020. DDR2 is currently used the most. 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 32-bit operating system is only capable of utilizing 4gb of RAM. However a 64-bit operating system is capable of supporting much more memory.As compared to ROM, RAM is costlier.

## ROM

ROM (Read Only Memory) refers to a read only memory chip that cannot be written on or erased by the computer user without special equipment. 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.

## CMOS

CMOS stands for Complementary metal–oxide–semiconductor. This is a technology used in chips and analog circuits. Cmos
It doesn't lose it's 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.
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