I do not understand the difference between karma and fate; are they the same or different?
All the things happen is not a result of Karma. Actually in Buddhism there are Fivefold Niyama where as Karma Niyama is a just one of them.
The Fivefold Niyama is as follows
uthu-niyama: the caloric order, the climate of the geographical location.
bija-niyama: the germinal order, things you inherited from the genes.
kamma-niyama: the moral order, is the one you are talking about.
chitta-niyama: the psychical order.
Dhamma-niyama: natural phenomenal sequence. we all get old and we all die its a natural thing for all of us
more details: http://www.buddhivihara.org/niyama.htm
I don't know what tradition your word for 'fate' comes from, but I'll try to answer anyway.
Fate usually means something which happens that is decided in advance, perhaps something that's decided before you were born, perhaps decided by God.
Whereas Karma is what happens as a result of your actions or your choices.
I simply say it is the same, But buddha has taught it in the name of Karma.
Simply there is one rule in the world.
- If you do something you will get the return. (This is simply known as the rule of Nature) This has been there for all of the buddha sasana for millions of years.
ex: If you hit somebody he will get a chance to hit you, may be in the next life that doesn't matter
The Fivefold Niyama says the same principle. That is why buddha has told to do good deads, So the next one will help you.