There are types A (Japan), B (US), C (EU), D (India), E (France), F (Germany), G (UK), H (Israel), I (AU) and so on: in which all have a distinct plug shape and differences in prongs. Type A plug is just two straight prongs without a ground while Type B is nearly identical to A but with a ground connection and Type F has no ground attached to the outlet while Type E does, usually this is solved with a adapter (for electronics that are dual voltage and support 50/60Hz frequency).