Difference between store rewards cards and credit cards

Store reward cards and credit cards can appear similar and be used at the same places.  Although they are often confused they are quite different in the way that they are used.

Store reward cards collect points for purchases.  They are not the primary means for payment.  They can only be used in certain stores, although there has been the growth of rewards cards that cross over a number of shops and service providers.

Credit cards are a means of payment.  Although there are some credit cards that can only be used in certain stores (so called “store cards”) these are quite rare and most credit cards can be used at all stores, service providers and vendors who accept a certain brand of credit card, for example MasterCard or VISA.
Store cards are cards that are issued by a store or a brand that lend the money to their customers.  They grew from the practice of offering revolving lines of credit to their customers, and there are still credit cards that are limited to the use in that store.  However most credit cards are currently accepted at all places that accept the credit card in question although they will generally tend to offer better discounts and other offers at the store that runs the credit cards.
Some stores are offering allowing their store cards to automatically add on to their rewards program.  These hybrid cards are where the credit card becomes identical to the store rewards card, however they are a rare if growing, part of the credit card market.  Many credit card companies integrate general rewards programs, such as Air Miles, into their credit card offering.
Many credit cards have rewards programs on their cards.  These reward spending, although they do not tend to reward spending at any particular shop or store – unless those stores are operating the credit card.  What they are doing is encouraging the consumer to use the card as this means that the shop keeper pays a transaction fee for using the credit card.  By offering a reward to use the card the credit card company is in effect sharing the proceeds with the card user.
Store rewards cards are different from credit cards in that store rewards cards offer discounts for spending, but not the spending itself while credit cards are a way of allowing spending itself to be done.