A cardinal (or counting) number shows the quantity of something, e.g. 3 apples or 1200 search results
An ordinal number expresses the rank or position of an item in an ordered list or a comparison of items, e.g. 1st in line, 3rd repetition, or 22nd row
A nominal number is used to identify something, similar to a calling name, e.g. a post code or a phone number.