Topic Summaries

Overview of number systems

GCSE > Computer Science > Pearson IGCSE > GCSE Computer Science > COMPUTER SYSTEMS: Number systems > Overview of number systems
Previous Module
Next Module

COMPUTER SYSTEMS: Encoding and compression

COMPUTER SYSTEMS: Network topologies

COMPUTER SYSTEMS: Wired and wireless networks, protocols, and layers

COMPUTER SYSTEMS: Threats to computer systems and networks

COMPUTER SYSTEMS: Operating systems and utility software

ALGORITHMS AND PROGRAMMING: Types of data

ALGORITHMS AND PROGRAMMING: Producing robust programs

ALGORITHMS AND PROGRAMMING: Designing, creating, and refining algorithms

ALGORITHMS AND PROGRAMMING: Artificial Intelligence (AI)

  • There are three number systems you need to know: 
    • Denary (decimal) is the standard base-10 system used by humans, consisting of digits 0–9.
    • Binary is the base-2 system used by computers, consisting only of 0s and 1s; each binary digit (bit) represents an on/off or true/false state in hardware.
    • Hexadecimal is the base-16 system, using digits 0–9 and letters A–F to represent values 10–15; it provides a more compact and humanreadable form of binary.
  • Binary is used directly by computers, while hexadecimal simplifies the representation of binary values for programmers (e.g. colour codes, memory addresses). 
  • Conversions between denary, binary, and hexadecimal are common in programming, networking, and low-level computing tasks.

Unlock Overview of number systems

Subscribe to SnapRevise+ to get immediate access to the rest of this resource.

Premium accounts get immediate access to this resource.

Previous Module
Next Module