10/19/25, 12:35 PM GCSE Computer Science (OCR)
GCSE Computer Science (OCR) NEWEST VERSION WITH
COMPLETE QUESTIONS AND ACCURATE DETAILED ANSWERS
\VERIFIED 100% \LATEST UPDATE \BRAND NEW!!!
Arithmetic Logic Unit (ALU) Performs operations on data e.g. Addition, subtraction
Control Unit (CU) Coordinating activities of the CPU
Registers Quick, small stores of data within the CPU
Memory Address Register Holds memory address for data or a instruction about to be used
(MAR) by the CPU
Memory Data Register (MDR) Holds actual data or instruction
Accumulator Stores results of calculations in the ALU
Program Counter (PC) Holds memory address of the instruction for each cycle
Fetch The next instruction is retrieved by CPU from main memory
Decode The instruction is broken down and decided so computer can
understand
Execute The CPU performs what the instructions told
Embedded System A computer system built within a large device e.g. Camera,
washer, car
Volatile Memory loses its data when power of
Non-volatile Memory retains its data when power is lost
Read/write - function is to load open programs and
Random Access Memory
(RAM) operating system data currently in use - volatile
Can only be read, can't be changed, stores essential
Read Only Memory (ROM)
programs to be run in order to boot the computer -
non-volatile
A type memory that stores copies of frequently used
Cache
data, much faster than RAM, lower capacity - closer
to CPU
Collection of wires that carry signals between various
Buses
components of the computer system
Processes all of the data and instructions that make the system
Central Processing Unit (CPU)
work - can be
effected by clock speed, number of cores, cache size
/ 1/1
5
, 10/19/25, 12:35 PM GCSE Computer Science (OCR)
Clock speed How fast the computer does the FDE cycle
A memory management procedure needed when the
virtual memory
RAM is full so a temporary section is made which acts
like a part of RAM
Solid state storage, non-volatile, more reliable/durable
Flash memory
but can only be overwritten a limited number of times
Graphics Processing Unit Handles graphics and image processing
(GPU)
CD, DVD, Blue-ray
ADV: cheap,easy to transport
Optical storage
DIS: slow, less storage than hard drives, stored data
degrades over time, cannot be written over
Hard drives
Magnetic storage ADV: fast access, stores large amounts
of data, low cost DIS: not very
portable, easily be broken
USB, flash memory, SD
Solid State storage ADV: fast, small, light, easily potable, quiet
DIS: more expensive, storage capacity less, limited number
erase/write cycles
Data is stored on multiple servers in
a remote location ADV: secure, can be
Cloud stotage
accessed anywhere, no need to buy
DIS: needs internet, download and upload can be
effected by internet connection, less control if data is
held
essential software that links the hardware and other
Operating System
software together and generally manages the
computer system
Command-line Interface Text commands where user has to type in command
Graphical User Interface (GUI) uses icons and other visual indicators to navigate and issue
commands
Utility Software maintains a computer
reorganises data on the hard drive to put fragmented
Defragmentation Software
files back together and moves files to collect all the
free space
Full Backup - a copy is taken from from every file on the system
Backup Software
Incremental Backup - only files created or edited since last
/ 2/1
5
GCSE Computer Science (OCR) NEWEST VERSION WITH
COMPLETE QUESTIONS AND ACCURATE DETAILED ANSWERS
\VERIFIED 100% \LATEST UPDATE \BRAND NEW!!!
Arithmetic Logic Unit (ALU) Performs operations on data e.g. Addition, subtraction
Control Unit (CU) Coordinating activities of the CPU
Registers Quick, small stores of data within the CPU
Memory Address Register Holds memory address for data or a instruction about to be used
(MAR) by the CPU
Memory Data Register (MDR) Holds actual data or instruction
Accumulator Stores results of calculations in the ALU
Program Counter (PC) Holds memory address of the instruction for each cycle
Fetch The next instruction is retrieved by CPU from main memory
Decode The instruction is broken down and decided so computer can
understand
Execute The CPU performs what the instructions told
Embedded System A computer system built within a large device e.g. Camera,
washer, car
Volatile Memory loses its data when power of
Non-volatile Memory retains its data when power is lost
Read/write - function is to load open programs and
Random Access Memory
(RAM) operating system data currently in use - volatile
Can only be read, can't be changed, stores essential
Read Only Memory (ROM)
programs to be run in order to boot the computer -
non-volatile
A type memory that stores copies of frequently used
Cache
data, much faster than RAM, lower capacity - closer
to CPU
Collection of wires that carry signals between various
Buses
components of the computer system
Processes all of the data and instructions that make the system
Central Processing Unit (CPU)
work - can be
effected by clock speed, number of cores, cache size
/ 1/1
5
, 10/19/25, 12:35 PM GCSE Computer Science (OCR)
Clock speed How fast the computer does the FDE cycle
A memory management procedure needed when the
virtual memory
RAM is full so a temporary section is made which acts
like a part of RAM
Solid state storage, non-volatile, more reliable/durable
Flash memory
but can only be overwritten a limited number of times
Graphics Processing Unit Handles graphics and image processing
(GPU)
CD, DVD, Blue-ray
ADV: cheap,easy to transport
Optical storage
DIS: slow, less storage than hard drives, stored data
degrades over time, cannot be written over
Hard drives
Magnetic storage ADV: fast access, stores large amounts
of data, low cost DIS: not very
portable, easily be broken
USB, flash memory, SD
Solid State storage ADV: fast, small, light, easily potable, quiet
DIS: more expensive, storage capacity less, limited number
erase/write cycles
Data is stored on multiple servers in
a remote location ADV: secure, can be
Cloud stotage
accessed anywhere, no need to buy
DIS: needs internet, download and upload can be
effected by internet connection, less control if data is
held
essential software that links the hardware and other
Operating System
software together and generally manages the
computer system
Command-line Interface Text commands where user has to type in command
Graphical User Interface (GUI) uses icons and other visual indicators to navigate and issue
commands
Utility Software maintains a computer
reorganises data on the hard drive to put fragmented
Defragmentation Software
files back together and moves files to collect all the
free space
Full Backup - a copy is taken from from every file on the system
Backup Software
Incremental Backup - only files created or edited since last
/ 2/1
5
