# StackExchange | | **Stack Exchange** is a network of question-and-answer (Q&A) websites on topics in diverse fields, each site covering a specific topic, where questions, answers, and users are subject to a reputation award process. The reputation system allows the sites to be self-moderating. As of March 2023, the three most actively-viewed sites in the network are Stack Overflow, Unix & Linux, and Mathematics. | | ---- | ---- | | | wikipedia:: [Stack Exchange](https://en.wikipedia.org/wiki/Stack_Exchange) | | | url:: [Stack Exchange](https://stackexchange.com/) |