A raven is a big black bird, (Corvus corax). It is also called the common raven or the northern raven. It is similar to a crow, but bigger. It and the thick-billed raven are the two largest birds in the crow family, and perhaps the heaviest perching birds. The raven's feathers are all black, but a crow has feathers that are white at the bottom. This cannot be seen from a distance.
The most famous raven is in the Edgar Allan Poe story called The Raven.