Usually new people listening to the music without any proper lyrics / spoken words in it, get confused about the genre/type/category of the music and consider it to be generally as techno or trance. However there is significant difference between the two!
To summarize, techno is the type in which there is mainly beats and non-rhythm continuous same type of music with not many layers. So it feels more like repetitive music.
However, trance is with multiple layers of music, which can be altered/changed to give a varying degree of sound effect and melodies. It has a rhythm and a beautiful flow.
Techno is like the music, that a person will like to forget himself and will start jumping and dancing over it!
Trance is more like a music to brain, and the body and mind soothes with it. Although dance is also done with it, but it’s soothing instead of forgetting sort of.
As an example, check these out on youtube:
Techno: Jeff Mills – “The Extremist (Retro Mix)”
Trance: Sonic Inc. – “The Taste Of Summer”
Hope it helped to know the main difference in both!