What is the difference in an angiosperm and a gymnosperm?

Answer 1

Definitions:

sperm: seed

gymno- : naked

angio- : vessel

So, gymnosperms produce naked seeds whereas angiosperms produce enclosed seeds.

Gymnosperms include the cycads, conifers and ginkos - all other plants are angiosperms.

Extra Credit

The Gymnosperms evolved first, before there were any land animals, seed dispersal was geophysical (e.g. wind, water, rolling down a hill) - when animals colonised the land plants evolved more complex ways of dispersing their seeds, enclosing them in burred shells, fleshy fruit, etc.