okay we'll start with techno. its jus basically a darker type of trance, doesnt have the fast hi hats or low bassdrums and has a normal bassline. - eg dj execute - megamix

Hardstyle is the second darkest, it can have fast hi hats and always has strong basslines, has few bassdrums. eg - zatox - noisemaker

Rave is the high speed type of techno, no bassline, jus high pitch noises, many bassdrums. eg- the pitchers - black is back

house is like a slow trance but with blended drum beats, e.g rock your body by black eyed peas.

Hope that helps :D i listen to a lot of electro so im telling from experience.

Note: chacarron is not an electro song, evn if u speed it up -,-#