1.2.1 - Primary storage (memory) Flashcards
Why do computers have primary storage?
Primary storage is a computer’s high speed, internal, main memory, that the CPU can access quickly and directly.
What are the two main types of primary storage?
RAM and ROM
What does volatile mean?
Data is lost when the power is turned off.
What is RAM?
Random Access Memory, which stored data and programs currently being used by the CPU.
What is ROM?
Read Only Memory, which permanently stores essential data.
What are the key characteristics of RAM?
Volatile - data is lost when power is turned off, it is temporary.
Holds the operating system, programs and data in use by the CPU when currently in use by the computer.
Memory can be written to and read from.
What are the key characteristics of ROM?
Non-Volatile - data is NOT lost when power is turned off, it is permanent.
Stores the startup instructions (bootstrap) to load the operating system when computer is turned on.
(+ stores BIOS)
Memory can only be read from.
What is virtual memory?
When RAM is full, a part of the hard drive is used as virtual memory as temporary storage.
Why may virtual memory be needed in a computer system?
Virtual memory may be needed in a computer system with limited RAM capacity, where larger applications and systems may need more memory space that available.
How does the transfer of data in virtual memory work?
Programs are transferred out to virtual memory from the RAM when they are not currently being used and executed, and the programs are then transferred back to RAM from virtual memory when they are then needed again.
