Slack 

Slack is a workplace chat and collaboration product. The official mission is to make working life simpler, more pleasant, and more productive. Teams talk in channels around a project or topic, search old messages, and hook in other apps so the same thread can hold files, alerts, and customer work. Slack says it is built for “customer companies” and now sits inside Salesforce Customer 360. The company did not start as a chat startup. Stewart Butterfield, Cal Henderson, Eric Costello, and Serguei Mourachov formed Tiny Speck in 2009 to make the game Glitch. After the game closed, the team’s internal tools became Slack, which launched publicly in 2013. Slack listed on the NYSE in 2019. Salesforce bought the company in 2021. The LinkedIn URL still uses the old legal name tiny-spec-inc. Headquarters is San Francisco. Official pages say Slack has more than 200,000 paid customers and is used in 150-plus countries, including most of the Fortune 100. There is a marketplace of thousands of apps. Recent work is about AI agents sitting in the same workspace as people, plus security for internal teams and outside partners.