Today after lecture in class today were the Lecturer was teaching about Ram under PC UPGRADE AND MAINTENANCE this is my conclusion drawn from it and a summary of a computer RAM
RAM stands for Random Access Memory. It refers to a common type of computer memory which can be accessed randomly. It is mainly of two types – Static RAM and Dynamic RAM.
RAM stands for Random Access Memory.
RAMS are generally classified into SRAM and DRAM.
SRAM – It stands for Static Random Access Memory. Flip flops are used for retaining memory by SRAM.
DRAM – It stands for Dynamic Random Access Memory. It makes use of a transistor and a capacitor to form a memory cell standing for a single bit of data. They are not able to retain information for a longer time even if the power supply is on throughout.
Apart from SRAM and DRAM, some other types of RAM are –
FPM DRAM – It stands for Fast Page Mode Dynamic Random Access Memory. 
EDO DRAM – It stands for Extended Data Output Dynamic Random Access Memory.
SDRAM – It stands for Synchronous Dynamic Random access memory.
DDR SDRAM – It stands for Double Data Rate. SDRAM were introduced in order to give an alternative to Single Data Rate SDRAM.
DDR2 SDRAM – In 2003, DDR2 SDRAM emerged. It stands for Double Data Rate type 2 SSDRAM.
DDR3 SDRAM – Double Data Rate Type 3 Synchronized Dynamic Random Access Memory.
DDR4 SDRAM – Double Data Rate Type 4 Synchronous Dynamic Random Access Memory. This RAM is a higher speed successor to the technology used by DDR3..
Apart from Rams there is NVRAM ( NON VOILIATE RADOM ACEESS MEMORY)
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