Tiny Speck developed Slack from an internal communication tool used while creating the game Glitch.
Stewart Butterfield and his team built the messaging system to coordinate work on Glitch, a browser-based multiplayer game. When Glitch closed in 2012, the team recognized that its internal communication software had broader potential than the game itself.
Tiny Speck released Slack in 2013, and the product quickly became known for organized channels, searchable messages, file sharing, and integrations with other workplace tools. The company later adopted Slack as its corporate name.
Slack is often described as an email replacement, but it is more precisely a channel-based collaboration platform. Salesforce announced an agreement to acquire Slack in 2020 and completed the acquisition in 2021, making Slack part of Salesforce’s enterprise software portfolio.