# Semaphore

Semaphore\. An object allowing not more than n [threads](https://pvs-studio.com/en/blog/terms/0048/) to enter the given code section\. The definition is offered by E\. Deixtra\. There are several types of semaphores: count semaphore, binary semaphore \(a subtype of the count semaphore\) and competitive access semaphore or [mutex](https://pvs-studio.com/en/blog/terms/0034/)\.

## References

1. Wikipedia\. "[Semaphore \(programming\)](https://en.wikipedia.org/wiki/Semaphore_(programming))"