Computer Science A-Level
OCR 2026 | Study Guide,
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, Accumulator (ACC) Register that stores the results of calculations in the arithmetic logic unit.
ACID Rules A set of rules that protect the integrity of a database. These are atomicity,
consistency, isolation and durability.
Address Bus The pathway along which the memory address being loaded from or saved to is
transported.
Agile Software Development A method of developing software that aims to deliver rapid and flexible responses to
change as well as strong team cohesion and communication.
Algorithm A set of instructions that can be carried out to solve a problem.
Analysis The third stage of the waterfall model, in which research is done into the current
system and a new system is proposed, along with its requirements.
Application Layer The part of the TCP/IP stack that is responsible for getting the data and encoding it.
Arithmetic Logic Unit (ALU) The CPU component responsible for performing mathematical calculations and
logical comparisons.
Array/Vector Processor A processor which allows one instruction to be applied to multiple pieces of data at
once. This is also known as Single Instruction Multiple Data processing, or SIMD for
short.
Asymmetric Encryption Encrypting data using two keys, one public and one private, so only the intended
recipient of data can decrypt it even if someone were to intercept messages whilst
the keys are being set up.
Assembler Software that translates assembly language into machine code.
Assembly Language A low-level programming language where instructions have a one-to-one
relationship with machine code and are made up of opcodes and operands.
OCR 2026 | Study Guide,
Practice Questions,
Answers, Rationales &
Exam Review | Complete
Ethics Study Guide
Updated 2026 Questions and Answers
100% Verified Exam Prep and Comprehensive
Rationales
Included
, Accumulator (ACC) Register that stores the results of calculations in the arithmetic logic unit.
ACID Rules A set of rules that protect the integrity of a database. These are atomicity,
consistency, isolation and durability.
Address Bus The pathway along which the memory address being loaded from or saved to is
transported.
Agile Software Development A method of developing software that aims to deliver rapid and flexible responses to
change as well as strong team cohesion and communication.
Algorithm A set of instructions that can be carried out to solve a problem.
Analysis The third stage of the waterfall model, in which research is done into the current
system and a new system is proposed, along with its requirements.
Application Layer The part of the TCP/IP stack that is responsible for getting the data and encoding it.
Arithmetic Logic Unit (ALU) The CPU component responsible for performing mathematical calculations and
logical comparisons.
Array/Vector Processor A processor which allows one instruction to be applied to multiple pieces of data at
once. This is also known as Single Instruction Multiple Data processing, or SIMD for
short.
Asymmetric Encryption Encrypting data using two keys, one public and one private, so only the intended
recipient of data can decrypt it even if someone were to intercept messages whilst
the keys are being set up.
Assembler Software that translates assembly language into machine code.
Assembly Language A low-level programming language where instructions have a one-to-one
relationship with machine code and are made up of opcodes and operands.
