Memory Flashcards
What’s RAM?
Random Access Memory, used as main memory in a computer. It can be read and written to. It’s volatile.
Difference between volatile and non-volatile
volatile is temporary memory (needs power to keep data), but non-volatile is permanent memory (keeps data without power)
What is the main memory?
where all data, files and programs are stored while they’re being used
What happens when a computer boots up?
operating system is copied from secondary storage to RAM
What happens when software apps, documents and files are opened?
they’re copied from secondary storage to RAM. They stay in RAM until the files or apps are closed
what do computers have a limited amount of?
RAM, a apps are being opened RAM fills with data
what’s virtual memory?
secondary storage used as extra RAM
what happens when RAM is full?
computer moves data that hasn’t be used recently to a location on secondary storage (virtual memory)
when may virtual memory be needed?
if there are too many apps open at once or if a particularly memory-intensive app is being used
if the CPU needed to read data stored in virtual memory what must it do?
move the data back to RAM
how can virtual memory make a computer slow to respond?
when switching between apps or when using a memory-intensive app
what’s ROM?
Read Only Memory, non-volatile memory. It can only be read, not written o.
what does ROM often contain?
all the instructions a computer needs to properly boot up, these are called the BIOS (basic input output system)
what happens as soon as a computer is powered on?
the CPU reads the instructions from ROM. This tells the CPU to perform self checks and set up the computer up, see what hardware is present and copy the operating system into RAM
what do ROM chips often use?
flash memory, common type of non-volatile memory. Used in SD cards, USB sticks and solid state drives (SSDs).
