Year 9.1 Knowledge Organiser
E-safety
Identity Theft:
Crime stealing someone’s
identity and impersonating them
It is illegal and could cause distress to
someone
Social Engineering and Phishing:
Tricking someone into giving away their
personal details. Phishing is done over
an email
Digital Footprint:
The trail of data you create when
online visiting websites
Central Processing Unit (CPU)
Is used for processing data
(the brains of the computer)
Control Unit (CU)
Controls and monitors the hardware
attached to the system
Arithmetic Logic Unit (ALU)
Carries out the arithmetic and logical
operations
Instructions will be
fetched, decoded,
then executed
Memory
Random Access Memory (RAM):
➢ Temporary Memory
➢ Volatile – needs power to retain memory
➢ Stores the programs and data that is
currently in use
Logic Gates
Computer Science
Department
Binary (Base 2)
128-64-32-16-8-4-2-1
0
0
1
1
1011 = 8+0+2+1= 11
2
2
Hex
Base 16
3
3
Read Only Memory (ROM):
➢ Non Volatile – does not need power to retain
memory
➢ Tells the computer how to start
Virtual Memory:
➢ When the RAM is full
➢ Secondary storage is used as temporary RAM
➢ Data is moved to VM and back to RAM when
needed
Networks
Two or more computers connected together to
share resources
Topology:
The arrangement of a network
AF
A
F
4
4
10
15
5
5
1010
1111
6
6
7
7
8
8
9
9
10101111
Database:
Table:
Collection of related data held in a
structured format
Little Man Computer
(LMC)
CPU Simulator
*peterhigginson.co.uk/LMC
A 10
Query:
Ask your database a question
B 11
Report:
Displaying the results of your queries
D 13
Structured Query Language (SQL):
Manipulating a database
C
ADD
INP
DAT
SUB
OUT
BRZ
Sound Representation
Sound is stored in binary
Sample rate - the number of audio samples captured
every second
Bit depth - the number of bits available for each clip
Bit rate - the number of bits used per second of audio
STA
BRP
BRA
LDA
HLT
12
E
14
F
15