1. |
Full Form |
RAM stands for Random Access Memory. |
HDD stands for Hard Disk Drive. |
2. |
Also known as |
RAM is also known as primary memory. |
HDD is also known as secondary memory. |
3. |
Type of storage |
The data is temporarily stored in this type of memory. |
The data is permanently stored in this type of memory. |
4. |
Components |
RAM does not contains, mechanical parts, only electronical parts like transistors. |
HDD contains moving mechanical parts, like the arm. |
5. |
R/W Time |
RAM has shorter R/W time. |
HDD has longer R/W time. |
6. |
Volatile |
RAM is a volatile memory. That implies a constant power supply is required for maintaining the contents of the memory. |
HDD is a non-volatile memory. That implies a constant power supply is not required for maintaining the contents of the memory cell. |
7. |
Memory Access |
In RAM each and every element takes same time to be accessed. |
In HDD different elements take different time to be accessed. |
8. |
Size |
In a system the RAM is smaller than the HDD. |
In a system the HDD is larger than the RAM. |
9. |
Cost |
RAM is costlier per unit storage. |
HDD is cheaper per unit storage. |
10. |
Noise |
RAM does not produces noise. |
HDD can produce noise due to mechanical movements. |
11. |
Duration of Data |
Data stored in RAM is temporary. It remembers as long as it has electricity, i.e. the power is on. |
Data stored in HDD is permanent, i.e. it retains data even after shutdown. |
12. |
Speed of Computer |
Inadequate RAM slows down the speed of the computer. |
HDD does not affect the speed of the computer. |
13. |
Form |
There are two form factors of RAM-
- For Desktops and Servers- DIMM (Dual In-line Memory Module)
- For Laptops- SO-DIMM (Small Outline DIMM)
|
There are two form factors of HDD-
- For Desktop Computers- 3.5 inch
- For Laptops- 2.5 inch
|
14. |
Usage |
To increase the speed of the computer. |
To increase the space for storing data or contents of the computer. |
15. |
Clearing of memory |
After running of particular program or application, the memory is cleared. |
The memory is not cleared while in use or even after use by an application or program. |
16. |
Speed |
The speed of accessing data is faster than HDD. |
The speed of accessing data in HDD is slower as compared to RAM. |
17. |
Example of existence in different forms |
- Static RAM (SRAM)
- Dynamic RAM (DRAM)
|
- Hard disk (magnetic)
- Floppy disk (magnetic)
- Tape drive (magnetic)
- CD-ROM or DVD-ROM (optical)
|