What is RAM?
The full form of RAM is Random Access Memory. The information stored in this type of memory is lost when the power supply to the PC or laptop is switched off. The information stored in RAM can be checked with the help of BIOS. It is generally known as the main memory or temporary memory or cache memory or volatile memory of the computer system.
In this Operating system tutorial, you will learn:
- What is RAM?
- History of RAM
- Types of RAM
- SRAM VS DRAM
History of RAM
Here, are important landmarks from the history of RAM:
| Type of RAM | Year Invented |
| FPM-(Fast page mode RAM)- | 1990 |
| EDO RAM (Extended data operations read-only memory) | 1994 |
| SDRAM (Single dynamic RAM) | 1996 |
| RDRAM (Rambus RAM) | 1998 |
| DDR (Double Data Rate) | 2000 |
| DDR2 | 2003 |
| DDR3 | 2007 |
| DDR4 | 2012 |
Types of RAM
Two main types of RAM are:
- Static RAM
- Dynamic RAM
Static RAM
Static RAM is the full form of SRAM. In this type of RAM, data is stored using the state of a six transistor memory cell. Static RAM is mostly used as a cache memory for the processor (CPU).
Dynamic RAM
DRAM stands for Dynamic Random Access Memory. It is a type of RAM which allows you to stores each bit of data in a separate capacitor within a specific integrated circuit. Dynamic RAM is a standard computer memory of the many modern desktop computers.
This type of RAM is a volatile memory that needs to be refreshed with voltage regularly. Else it loses the information stored on it.
SRAM VS DRAM
| SRAM | DRAM |
| SRAM has lower access time, so it is faster compared to DRAM. | DRAM has higher access time, so it is slower than SRAM. |
| SRAM is costlier than DRAM. | DRAM costs less compared to SRAM. |
| SRAM requires a constant power supply, which means this type of memory which consumes more power. | DRAM offers reduced power consumption because the information is stored in the capacitor. |
| It is a complex internal circuitry, and it offers less storage capacity is available compared to the same physical size of a DRAM memory chip. | It is the small internal circuitry in the one-bit memory cell of DRAM. The large storage capacity is available. |
| SRAM has a low packaging density. | DRAM has a high packaging density. |