There is different terminology in the US and the UK. Now I will probably confuse myself trying to explain:
Crisps = UK word for potato snacks that come in a bag
Chips = US word for similar snacks in a bag, these can be potato chips, or corn chips.
I don't know how you express these in Spanish, it seems there is a lot of regional variation between different Spanish speaking countries having looked online (maybe 'patatas de bolsa'?, that's a guess by the way)
Chips (UK) = patatas fritas
French fries (US) = patatas fritas
But to complicate things further, we have French fries in the UK too, they're longer and thinner and the kind you get in fast food restaurants like McDonalds. Normal 'chips' are wider and shorter. If you look for images it will probably enable you to see the differences more easily than any words will.