Yes. They're both in the same genus (Corvus), but are different species... of course, that's referring to the crows/ravens in North America anyway, there may be birds referred to as crows and ravens elsewhere that aren't in the same genus. That's the fun of common names versus taxonomic names :)

Common crow - Corvus brachyrhynchos - medium sized black bird, relatively sleek with squared tail; caws
Northern Raven - Corvus corax - larger medium sized black bird, bulky, shaggy around the bill, wedge-shaped tail; call is more like a hoarse croak

There are other crow and raven species in North America (2 more crows and another raven), but these are the ones generally referred to.