Slack began as the chat tool a small game studio built for itself while it made a game that failed. The studio was Tiny Speck, run by Stewart Butterfield, who had co-founded Flickr. When the game shut down, the team kept the chat tool and sold it. By 2019 offices ran on Slack channels, emoji reactions and endless notifications. Slack skipped the usual IPO and listed its shares directly.

What Was Left of Glitch

Butterfield and his co-founders started Tiny Speck in 2009 to build Glitch, an online game. Glitch closed in 2012. The team had built an internal messaging tool along the way, and they bet that other teams would want it too. Slack launched to the public in 2014. It organized talk into channels by topic, kept every message searchable, and plugged into other work apps.

A Direct Listing on WORK

Slack went public through a direct listing on the New York Stock Exchange on June 20, 2019, under the ticker WORK. It sold no new shares. The exchange set a reference price of $26. The stock opened at $38.50 and closed at $38.62. Microsoft Teams then grew fast by bundling chat with Office. In July 2021 Salesforce completed its purchase of Slack for about $27.7 billion.

Cover: Three Gossips, Honoré-Victorin Daumier. Art Institute of Chicago, public domain. Chosen for office gossip (workplace chat).