what are the 2 primary memory? | RAM, ROM |
what does RAM stand for? | random access memory |
What is the use of RAM | it stores currently-in-use data. It is a volatile memory. It can be read from and written to |
what is volatile memory? | temporary memory |
what happens as RAM gets full? | processor has to access Hard-Disk-Drive to replace old data on RMM with new data |
as RAM increase, what happen? | faster the computer. RAM will never run out, it just gets slower overtime |
what does ROM stand for | Read Only Memory |
What is ROM use? | non-volatile memory used to store startup instruction for a computer system (BIOS). It can only be in read form |
Why SSD over HDD? | 1. faster data access
2. more reliable (no moving parts)
3. thin and lighter in weight
4. don't heat up as much |
What is A, B, C and D? | A= Track
B= Geometrical Sector
C= Track Sector
D= Custer |
What does HDD stand for? What does it make use to store data? | Hard Disk Drive. It makes use of magnetic disk to store data |
How does HDD work? | 1. has number of platters which spin in 7000 times per second
2. Number of read-write heads have access to surface of platter
3. read-write heads move from center to edge 50 times per second
4. data is stored in sectors and tracks. Each sector has number of bytes |
What is the disadvantage of HDD? | 1. latency
2. not suitable for high magnetic field environment
3. not suitable for moving environment
4. loud |
What is optical storage? | storage of data on an optically readable medium |
What does CD and DVD stand for? | Compact disk, digital versatile disk |
What is SSD stand for and what does it make use of? | Solid state drive, makes use of movement using electron (flash technology)(NAND chips) |
What are the uses of secondary storage | Store software and files (non-volatile) |
What are 4 similarities of CD and DVD | 1. use a thin layer of metal and light sensitive organic dye to store data
2. both use single, spiral track which runs from center to edge of disk. On track, data is stored as pits and bumps
3. uses red lasers
4. both designated for R(write once) and RW(read and write multiple times) |
How are DVD different from CD? (2) | 1. DVD has two layers (larger storage capacity)
2. two layers join together using transperant, polycarbonate spacer and thin reflector |
What lasers does blue-ray use? What does it do? | blue lasers, increase storage capacity because allows smaller pits and bumps |
What does blue-ray disk come with? (security) | encryption system, prevent copyright and copyright infringement |
Describe blue-ray layers | single polycarbonate layer, which avoids refraction of lasers |
What is the advantages of USB flash memory? | 1. universal standard
2. only inserted one way, prevent incorrect connection
3. small portable
4. detects if correct driver installed |
Describe magnetic off line storage | e.g. external hard disk drive
-use as backup or transfer of large files between devices |
Describe solid-state storage | e.g RAM stick, SSD, SD card
-no moving parts (high speed flash memory)
-quick data transfer
-small |