People often ask about the types of bees that exist. The simple answer is there are a really really large number of bee species – at least 20 000 with more than 4000 in the US.
Bees evolved from some ancient wasp that was a predator. Somewhere along the evolutionary footpath, bees shifted from eating insect protein to pollen protein.
Bees are a very varied group of insects. What we need to do here is really just to give you a very broad overview of what the different major types of bees are.