The need for primary storage

1.2.1 Primary Storage (memory)

Primary Storage (memory) — Note 1 of 6

What you need to know

Primary storage (main memory) is the computer's workspace for actively running programs. It provides fast access to data and instructions currently in use by the CPU. Without primary storage, the CPU would need to constantly retrieve data from much slower secondary storage.

What to know

Primary storage usually consists of RAM and ROM.
It provides FAST access compared to secondary storage, allowing the CPU to process instructions quickly.
Without primary storage, the CPU would have to read from slower secondary storage (e.g. hard drive) for every instruction, making the computer extremely slow.

Key terms

Exam tipCommon mistake

Primary Storage: Fast memory directly accessible by the CPU that holds data and instructions currently in use.
Exam tip: The key reason for primary storage is SPEED — it provides fast access to currently needed data and instructions.

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