1-Click, also calle one-click or one-click buying, refers to the technique of allowing customers to make online purchases with a single click, with the payment information needed to complete the purchase already entered by the user previously. More particularly, it allows an online shopper using an internet marketplace to purchase an item without having to use shopping cart software. Instead of manually inputting billing and shipping information for a purchase, a user can use one-click buying to use a predefined address and credit card number to purchase one or more items.