Definitions: Fundamentals of Computer Systems: Computer Science Paper 2: A-Level AQA

Hardware

Physical components of a computer system.

Software

Program or data run by a computer.

Application Software

Allows users to perform specific tasks.

System Software

Manages technical aspects of a computer system.

Assemblers

Translate assembly language to machine code.

Compilers

Convert high-level language to machine code.

Interpreters

Check syntax errors, translate source code to machine code.

Libraries

Pre-compiled programs loaded when needed.

Operating System

Manages computer operation, bridges user to hardware.

Translator

Converts code between computer languages.

Utility Program

Performs common user tasks like analysis or optimisation.

Resource Management

Efficiently manages hardware and software for system performance.

Scheduling

Allocates processor time for efficient multitasking.

Assembly Language

Low-level language corresponding to machine code.

High-Level Language

Abstracted, human-readable programming language.

Imperative Languages

Use subroutines to change program state.

Low-Level Language

Little abstraction from processor's instruction set.

Machine Code

Binary language directly understood by CPU.

Bytecode

Intermediate instruction set for compiler output.

AND (∧)

Returns TRUE if all inputs are TRUE.

NAND

Returns FALSE if all inputs are TRUE.

NOR

Returns FALSE if at least one input is TRUE.

NOT (¬)

Returns TRUE if input is FALSE.

OR (∨)

Returns TRUE if at least one input is TRUE.

XOR

Returns TRUE if exactly 1 input is TRUE.

Absorption Laws

Rules for combining logical operations.

Association Laws

Rules for grouping logical operations.

Boolean Expressions

Combination of boolean variables and operators.

Boolean Logic

Algebra with logical operators reducing to TRUE or FALSE.

Commutation Laws

Rules for changing order of logical operations.

Distribution Laws

Rules for distributing logical operations.

Idempotence Laws

Operations with the same input and output.

Inverse Laws

Operations resulting in 0 or 1.