A Level Computer Science OCR Practice Exam 2025 – Complete Study Resource

Character sets are fundamental to how data is represented in computer systems, as they define the mapping between characters (like letters, numbers, and symbols) and the numerical values used to store and process these characters. When a computer processes text, it does so by referring to a specific character set that translates each character into a corresponding binary number, which is ultimately how data is stored in memory.

For example, the ASCII character set uses values from 0 to 127 to represent standard English letters, digits, punctuation marks, and control characters. This enables consistent text representation across different systems and platforms, allowing programmers and applications to ensure that the text displayed is accurately reflected by the binary data stored.

The other choices do not accurately describe character sets. Numerical values used in calculations pertain more to data types like integers or floats, not characters. Programming commands relate to the syntax and instructions of a programming language, while encryption algorithms involve methods for securing data, not representing characters. Therefore, the definition of character sets as sets of symbols representing data in computer systems is the most accurate.