PayPal is a global e-commerce business allowing payments and money transfers to be made through the Internet. Online money transfers serve as electronic alternatives to paying with traditional paper methods, such as checks and money orders.
Originally, a PayPal account could be funded with an electronic debit from a bank account or by a credit card at the payer's choice. But some time in 2010 or early 2011, PayPal began to require a verified bank account after the account holder exceeded a predetermined spending limit. After that point, PayPal will attempt to take funds for a purchase from funding sources according to a specified funding hierarchy. If you set one of the funding sources as Primary, it will default to that, within that level of the hierarchy (for example, if your credit card ending in 4567 is set as the Primary over 1234, it will still attempt to pay money out of your PayPal balance, before it attempts to charge your credit card). The funding hierarchy is (1) a balance in the PayPal account; (2) a PayPal credit account, PayPal Extras, PayPal SmartConnect, PayPal Extras MasterCard or Bill Me Later (if selected as primary funding source) (It can bypass the Balance); (3) a verified bank account; (4) other funding sources, such as non-PayPal credit cards.