“Crow” is a common name for all birds in the genus Corvus. They are a subgrouping of corvids. In Australia, there are three native species called crows – the Torresian crow (in northern, tropical areas), the Bismarck crow (closely related to the Torresian one, limited to the Bismarck Archipelago) and the little crow (in western and central Australia). Australian ravens are also technically varieties of crow, but I guess biologists in Australia decided to use the word “crow” for one of the two major subgroupings of Australian corvids, and “raven” for the other. Globally, there is not really a strict division between “ravens” and “crows”.
Crows in general, like other corvids, are extremely intelligent birds, and have been known to use tools, operate water taps, throw away litter into bins (!), and are also generally very playful. They are also pretty good at recognising and distinguishing between different humans, and will show loyalty to humans who have been nice to them. Apparently they have different regional dialects, and have been known to hold funerals for their deceased.
There are many different varieties of crows but they seem to have lifespans of about 20 years. They are opportunistic eaters, omnivorous, and have been known to scavenge carrion (some varieties more than others).
Crow is also the name of an important figure in many Australian Aboriginal mythologies.