We offer American and European style options. The main difference between these two styles is the way the options are settled. With an American style option, a physical delivery of the underlying asset takes place on expiration date. With European style options, a cash settlement takes place, hence, cash is settled on the expiration date.
A second difference is that with American style options it is possible to exercise the option before the expiration date (early exercise). This means that the holder of the option can decide to exercise the option at any time and can therefore call for the shares or must deliver them.
Whether the options are American style or European style has no link to the place where the options or underlying assets are traded. Stock options are almost always American style. Index options are often European style.
More information with regard to this topic can be found here.