The Hopper (Morvan) Drives were first mentioned in the movie novelization, as well as the Confederation Handbook.
They are called Hopper Drives, because they're used to "hop" between relativelly close stars.
They were used by Pilgrim explorers, but they were unreliable, and had short range. They were invented late in the 22nd century, and what they did was create a gravity well (sort of) that could be jumped through like the Quasars in the movie. But it had a very short range (25/30% of a light year), and the risk was to great, plus it had many limitations (like you couldn't activate it near an object with their own gravity, and you couldn't activate the drive for at least 18 hours since the last "hop").
In Pilgrim Stars however, Pilgrims have developed a new type of Hopper Drives under Confeds eyes, this one was much more safer, and had a much greater distance, and the gravity well it made could be used as a weapon that could even swallow entire planets.
Confed allowed Pilgrims to produce this new drive, because they wanted to take it for themselves once it was completed. The Pilgrims however knew that Confed was watching them, and they completed the drive before Confed was ready to stop them