Credit card

 

Credit card (1)   is the sign currently used. This sign is undergoing semantic change, due to technology,

to cover a broader meaning.  It can be used for a “coded card”, a “digital card”, or a “key card” e.g. a key card

for unlocking a door,  a key card for unlocking a computer, etc.

 

Credit card (2)  (old) is an old sign.