Beginner Gardening: Hippeastrum is Amaryllis?, 1 by Shlomit

Shlomit wrote:
Hello,
I was looking in Wiki and also in other places, and understood that Hippeastrum and Amaryllis are two different plats, one comes from tropical and subtropical regions of America and the other comes from South africa.

http://en.wikipedia.org/wiki/Hippeastrum
http://en.wikipedia.org/wiki/Amaryllis_belladonna

Is this true?
Because when I searched DG for Hippeastrum, I saw many flowers names that contains the two kinds, like
"PlantFiles: Amaryllis
Hippeastrum striatum"

This got me confused because if its not the same plant how come it have the both plant names?
It also said:
"Amaryllis is a small genus of flowering bulbs, with two species. The better known of the two, Amaryllis belladonna"

I'll be grateful to learn about it,
Thank you very much
Shlomit

Attached: Hippeastrum at my Balcony (I don't know the kind)