Pegasus is the winged-horse which sprung from the blood of the slain Medusa, killed by Perseus. Pegasus' father was Poseidon, God of the Sea.
This autumnal constellation has some fine objects for telescopes, and a few for binoculars as well, such as M15, a splendid globular cluster.
The constellation is 'joined' with Andromeda as the common star Alpheratz serves not only as alpha Andromedae but also as delta Pegasi.
The Great Square of Pegasus, one of Autumn's notable signs, is first seen in mid-Summer if you face the east around 1 a.m. It'll be found between Deneb (alpha Cygni) and the horizon, standing on one of its corners (gamma Peg).
Click on alpha Pegasi, delta or epsilon Pegasi.