Primary Memory |Types of Primary Memory |Go My Class

Primary Memory

Primary memory is also called main memory or internal memory. It is unstable memory because it can store data for a short time and all data is erased while the computer is shut down. Primary memory only store data or instructions in which the computer is working. The storage capacity of primary memory is limited but it has very high data processing capacity due to which applications and programs can be run easily.

There are two types of Primary Memory :~

1. RAM 2. ROM

RAM :~ The full name of RAM is Random Access Memory. RAM is also called temporary or volatile memory. Data is not stored in RAM, when the data comes in RAM from ROM or any other memory, then we are able to use it. If any video, music, game or application is run in the computer, then all these data are first loaded in RAM. After that we are able to use all the applications. RAM is faster than any other memory. Thereby reaching the data to processor quickly. So that any application of computer can be run faster.

There are two types of RAM :~

1. SRAM (Static Random Access Memory)

2. DRAM (Dynamic Random Access Memory)

1. SRAM :~ The full name of SRAM is Static Random Access Memory. SRAM is made of flip flop so it is less refreshed. As long as the computer is running, it stores the data, but all the data is automatically deleted when the computer is closed, but it can store the data for a longer time. SRAM is used as cache memory in computer systems. Which is very fast and small. SRAM is also called volatile memory.

2. DRAM :~ The full name of DRAM is Dynamic Random Access Memory. DRAM refreshes thousands of times in a second so its speed is slow. In DRAM, data is stored in a memory cell. Each memory cell has a transistor and a capacitor. In which the data is stored but the memory cell controller keeps refreshing the memory after 4 milli second i.e. the data keeps rewriting. New data is stored automatically in DRAM. DRAM is used as the primary memory in most personal computers.

ROM :~ The full name of ROM is Read Only Memory. ROM is a primary storage device in which the user saves all his data (audio, video, photos, documents). It is a non-volatile memory because the stored data in it does not delete or erase even when the computer is turned off. ROM is fixed program memory in which nothing can be changed. In this, the instructions of the basic functionality of the computer are written or stored by the developer or programmer at the time of manufacturing. Which cannot be deleted or modified. Can only be read. The ROM helps the booting process when the computer system is started (on).

There are three types of ROM :~

1. PROM

2. EPROM

3. EEPROM

1. PROM :~ PROM's full name is Programmable Read Only Memory. Data can be write only once in PROM. After that the PROM cannot be updated or erased. The PROM burner device is used to write data to PROM. The process of writing data in PROM is called PROM burning.

2. EPROM :~ The full name of EPROM is Erasable Programmable Read Only Memory. Ultraviolet rays are used to erase data in EPROM. When programming, data is stored in EPROM by electric charge. Which can be stored and kept for more than ten years. Because electric charge has no way out. Therefore, data is stored safely in EPROM.

3. EEPROM :~ The full name of EEPROM is Electrically Erasable Programmable read only memory. In this, the data is erased by electric charge. EEPROM can be erased about 10 thousand times. EEPROM does not have to be taken to a developer or programmer to erase because the data can be erased in the computer through a particular software and the data can be reprogrammed again and again. In EEPROM, data can be stored for more than ten years.