A wiki is software that allows users to collaboratively create, edit, link, and organize content on a website. Wikis are often used to create collaborative websites and power community sites. Wikipedia, one of the largest wikis, is an online encyclopedia created and edited by thousands of users. Wikis offer benefits like easy collaboration, searchability, and low costs. They can help promote collaboration, establish institutional memory, enhance knowledge sharing, and cut down on email exchanges between coworkers. When implementing a wiki, considerations include accessibility, transparency, responsibility, and sensitivity of content.