Computing revision key areas

Computing revision key areas

1. Proprietary software

   • No source code
   • License agreement
   • Questions involving manufacturer
     • Can't be edited
     • Competitors
     • Compatability

2. Starts with 0 = string

3. Reliability

   • F
     • Failover policies: backup data, power cuts, server failures
   • C
     • Coding: bugs
   • S
     • Security: personal data

4. AND gate: both the same to be 1, otherwise 0

5. System information utility: temperature

6. Byte: 8 bits Nibble: 4 bits Bit: 1 bit

7. A variable is a value that can change while the program is running

8. A while loop doesn't have to iterate the first time

9. DBMS

   • Why desirable: quick search and retrieval of information from a database, data can be organized into tables that are easily reorganized for accessing data in different ways and they are very efficient in terms of processing capacity especially over a network.

10. Validation: list check

11. Virtual memory: stored in secondary storage, needed when not enough RAM, used as RAM to store RAM.

12. Stored in RAM: OS, programs currently in use

13. One purpose of HTML: links to images

14. Secondary storage

    • Cost
      • Best: optical Worst: SS
    • Durability
      • Best: flash and SS Worst: optical
    • Portability
      • Best: flash and optical Worst: Magnetic
    • Capacity
      • Best: Magnetic Worst: Optical
    • Data transfer speed
      • Best: flash and SS Worst: optical
    • Energy consumption
      • Best: flash and SS

15. Non volatile data stores:

    • P
      • Programs
    • O
      • Operating system
    • F
      • Files

16. The router connects a LAN to the Internet

17. Peer to peer: connects nodes, equal status

18. Automatic update: searches manufacturer's website, downloads if found

19. Opcode and operand

    • Opcode
      • Instruction
    • Operand
      • Location, eg register

20. Machine code is designed to be read by computers and is harder to be understood by humans that higher level code.