Snap went public in 2017 and gave its new shareholders no voting rights at all. It was the largest tech offering since Alibaba. The company built Snapchat, the app that made photos vanish. Young people used it to talk in pictures instead of text, and rivals soon copied its Stories format. Snap called itself a camera company. It made its money selling ads between friends' posts.

Turning Down Facebook

Evan Spiegel and Bobby Murphy started the app in 2011, while Spiegel was a student at Stanford. Its ghost logo hinted at messages that disappeared after viewing. The bet was that people wanted a place to share casual moments without a permanent record. That set Snapchat apart from Facebook. In 2013 Facebook offered to buy the company, and Spiegel turned it down.

Instagram Copies Stories

Snap priced at $17 a share in March 2017 and jumped on its first day. The stock soon fell as Instagram copied Stories and user growth slowed. Snap rebuilt its Android app, invested in augmented reality and launched Spectacles glasses. The share price swung widely over the years. Its daily users later grew to several hundred million people. Snap remains public, led by its founders.

Cover: Kohada Koheiji, from the series "One Hundred Ghost Tales (Hyaku monogatari)", Katsushika Hokusai. Art Institute of Chicago, public domain. Chosen for a ghost (Snapchat's ghost).