An expo (exposition) is really a type of exhibition. It means that we will probably see something related to modern technology. I even go to a Teacher's Expo every year to learn about new technology I can use to help me teach online. An exhibition is more vague. An exhibition is just a collection of exhibits, which means things on public display. So yes, unless you work for a tech company showing off their new inventions and gadgets, I would say exhibition. :) Let me know if you have any other questions. Good luck with your studies!

My thoughts: 'exhibition' implies it is passive and something you view only -- an art exhibition is where you go to look at art. An 'expo' has come to imply an interactive event where you go from booth to booth talking to people, buying things, etc.

An example: An event where it has many comic books, videogames... the Expo Geek!! This isn't a exhibition!!!