1.2 Memory And Storage Flashcards
What is memory ?
component of the computer that holds
data, programs and instructions that are currently in use.
What are the two types of Primary memory?
- ROM
- RAM
Which type of primary memory is volatile ?
RAM
Which type of Primary memory is non-volatile ?
ROM
What is the average size of Primary memory in a modern personal computer ?
4 GB
What is stored in ROM ?
- The BIOS
- Bootstrap
What is the purpose of the BIOS ?
- Checks hardware is functioning correctly
What is the purpose of the bootstrap ?
- Loads the computer’s operating system
What are the properties of RAM ?
- Data can be stored and accessed from any location within the memory
What does the RAM hold ?
- The OS
- Open documents and running programs
Can RAM be read from and written to ?
YES
What are the pros of having more RAM ?
more data and programs it can hold simultaneously
What is Virtual Memory ?
A section of a computer storage drive which is temporarily used as RAM.
What is swapping when using VM ?
The process of moving data between RAM and secondary storage when using virtual memory.
What are the effects of using VM ?
- Computer runs slowly
- Disk thrashing
What is secondary storage ?
Non-volatile memory external to the CPU and used for long-term storage of programs and data.
Why is secondary storage needed ?
to keep programs and data indefinitely.
What are the three common types of secondary storage ?
- Magnetic
- Optical
- Solid State
What are the properties of Magnetic devices ?
- Fairly cheap
- High capacity
- Durable
- Vulnerable to magnets and shock
How do magnetic devices work ?
- Use magnetised sections as 1
- As the disk spins a read/write head moves
How do optical devices work ?
- Use a laser to scan the surface
- flat areas = lands = 1
- hollows = pits = 0
What are the three types of optical media /
- ROM
- R
- RW
How do solid state devices work ?
use non-volatile RAM to store data indefinitely
What are the properties of solid state devices ?
- Fairly expensive
- High capacity
- High durability
- Portable
- Reliable
What are the 6 factors that determine the application of secondary storage ?
- Cost
- Capacity
- Speed of access
- Portability
- Durability
- Reliability
