# operating system

CEFR B1 · Compound

Source: https://englishreference.com/word/operating-system
Updated: 2026-07-22

## Definition

the main software that controls a computer or phone. It manages all the other programs and helps the hardware work with the software.

For teachers: the primary software that manages computer hardware, software resources, and provides common services for computer programs.

## Examples

- I need to update my operating system to the latest version.
- Most people choose their smartphone based on whether they prefer the Android or iOS operating system.
- The stability of an operating system is critical for server environments where even a few minutes of downtime can result in significant financial losses.

## Usage notes

- Often abbreviated as 'OS' in technical and informal contexts.

---

From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.