Star Trek: Every Hero Ship Ranked Worst To Best

The USS Discovery (introduced in Star Trek: Discovery) and it's sister ship, the USS Glenn, were Crossfield-class experimental starships, designed in the 23rd century primarily to test and perfect top-secret spore drive technology.

The spore drive, developed by Paul Stamets and his friend, Straal, allowed for instantaneous travel from one point in space to another by tapping into a universe-wide network of mycelium. It became functional when the crew realised that the drive needed to hook up to a living creature to interface with the network. Following the Klingon War, Starfleet ordered that the spore drive be decommissioned until a non-living interface could be developed, but Discovery was later allowed to use it to investigate the red bursts in season two.

At the end of the second season, Discovery travelled to the 32nd century, the ship and it's spore drive were classified under penalty of treason, and all research stopped until Discovery's return. In the 32nd century, Discovery received a number of advanced upgrades, such as a cloaking device, detached nacelles, and programmable matter. The ship also became self-aware after being possessed by the artificially intelligent Sphere Data (in season two), and eventually even picked it's own name: Zora.

Few ships have been through as many changes as Discovery. Watching the show over the past few years, we've gotten to see it evolve from a testing-ground for the spore drive, into one of the most experimental and unique hero ships in Starfleet history.