Passage: Google Glass is a brand of smart glasses—an optical head-mounted display designed in the shape of a pair of eyeglasses. It was developed by X (previously Google X) with the mission of producing a ubiquitous computer. Google Glass displayed information in a smartphone-like, hands-free format. Wearers communicated with the Internet via natural language voice commands.Google started selling a prototype of Google Glass to qualified "Glass Explorers" in the US on April 15, 2013, for a limited period for $1,500, before it became available to the public on May 15, 2014.  It had an integral 5 megapixel still/720p video camera. The headset received a great deal of criticism amid concerns that its use could violate existing privacy laws.On January 15, 2015, Google announced that it would stop producing the Google Glass prototype, to be continued in 2017 tentatively. In July 2017, Google announced the Google Glass Enterprise Edition. In May 2019, Google announced the Google Glass Enterprise Edition 2.

Question: What format did Google Glass display?
hands-free