Primary memory is a key component of a computer system. Its function is to hold data and programs that are currently in use.
Memory is the component of the computer that holds data, programs and instructions that are currently in use.
An explanation of RAM, ROM and virtual memory
Primary memory is built inside the computer. As a result, data can be read from and written to primary memory extremely quickly. This gives the processor fast access to the data and instructions that the primary memory holds.
There are two types of primary memory:
ROM is non-volatile, whereas RAM is volatile. Non-volatile memory keeps its contents even when the computer is switched off. Volatile memory loses its contents when unpowered.
Primary memory is comparatively limited in size, especially when compared with secondary storage. In a modern personal computer, primary memory is often around 4 GB in size.