SubPrime is higher risk. Banks such as Cap1, target people that probably won't be able to pay in full. They charge higher interest rates and sometimes, more than not, charge annual or monthly fees to have the card. Subprime cards generally have credit lines around $200-$500. Most of the time a person with better credit would not choose to get a card with an annual fee and a credit line of $200.
Prime is lower risk. These banks give higher credit lines to start because they feel you have earned it. These credit lines can be anything from $500 up to $200,000 and up. The interest rates are lower. Most of the time a person with lower credit scores would not be approved for prime cards until they have established them selves.
These rules don't always apply. Generally subprime is high interest, prime low interest. Some banks offer prime and subprime. Such as Cap1. Be careful, their prime cards might be seen as subprime because the main focus of the bank is subprime.
Another thing is subprime banks make more money on fees and interest and prime banks make more on transactions.
