Joint credit card allows two people to use the same credit card, commonly it works as an individual completes a completes a credit card application and then request for another card, the other card will have a second person named on it but will have the same account number assigned on it, it is commonly used by married couples.
There are lots of cases that married couple have joint credit card accounts to be able to do things such as savings, investment portfolios and checking, this way they are simplifying their management of finances, another typical reason for having a joint application credit card is a parent wanting to assist their children in establishing a good credit.
Both card holder has the responsibility of the paying the debt aquired by either of them, for example if the other holder runs up a $4000 debt on the card, even if the other holder is separated, he/she isn’t going to be relieved by that debt.
You will be held responsible for any all debts aquired as long as your name is still on the card, the only way to stop it is to pay all your debts in the card and cancel the card so there will be no further purchases made with it, canceling a joint credit card can actually be done individually, as long as the account is free of any outstanding debt.