Hi there, welcome to my blog. Here I present you some of the key differences between Primary and Secondary Memory.
| SN | Primary Memory | Secondary Memory |
| 1 | Any memory devices that’re connected directly to CPU or processor are referred to as Primary. | Memory that is not directly connected to processor, for processor to access secondary memory it need to go through primary memory. |
| 2 | Per unit storage cost of primary memory is high i.e. manufacturing cost is high because of technology and materials used. | Data storage cost of secondary storage devices are cheaper than the that of primary. |
| 3 | Response time is high and data/instructions can be accessed faster from Primary Memory. Majority of Primary Memory use Random Access mechanism. | Slower response time as compared to primary memory. They usually deploy the sequential access mechanism. |
| 4 | Content of Primary Memory can be accessed by using data bus. | Contents stored in Secondary memories are accessed by using Input/Output(I/O) channels. |
| 5 | Storage capacity is low. (generally between 1GB to 32 GB) | It stores a large volume of data( Generally storage capacity is measured in term of GB or TB. Generally more than 100 GB) |
| 6 | It is volatile in nature, means data cannot be retained if electricuty is cut-off. | Secondary Storage devices are non-volatile in nature and can hold the data even after power is cut-off. |
| 7 | Primary memories are used to store: – temporary data of programs that CPU is currently working on. – temporary data of programs that users are using frequently – startup programs that tell system the startup program sequence. | Secondary Storage devices can be used to store permanent contents like documents, movies, graphic works etc. |
| 8 | Main types of Primary Memory: a. RAM b. ROM c. Cache Memory d. Registers | Main types of Secondary Memory: a. Magnetic Storage Devices: Magnetic Tapes, Magnetic Disk(Hard Disk) b. Optical Storage Devices: CD, DVD, Blue-Ray Disks |
#Update1(2020):
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