Yoshi first appeared in
Super Mario World (SNES). In that game,
Mario rides on him, and Yoshi
darts out his very long
tongue, eating countless enemies without gaining any
weight, gaining you a coin for each one. It is unclear whether Yoshi refers
to the
species or the
individual dinosaur, as it is used like a
name, but it is used for every single one.
Yoshi was so
popular that an entire game was later dedicated to him (
Super Mario World 2: Yoshi's Island). In that, he tries to bring baby
Mario and
Luigi to their parents after they are kidnapped by baby
Bowser. This game has its own
sequel on the
N64, but I never played it.
Yoshi has been in every
Mario game since, even though it is often a minor
part. He comes a wide
range of colors, but is best known in his
green form. In
Super Mario World, different colored Yoshis have different abilities (
blue is the best). In Yoshi's Island, they are simply an
ethnically diverse but equal
population.