Sellers
Web sites and merchants can integrate Google Checkout into their sites as an alternative payment processing method to existing checkout and credit card processing systems.

Buyers
Consumers with a Google account can type their credit card and billing information into Google Checkout once and then pay for purchases thereafter with practically one click on any Web site

Any Web site can add Google Checkout as a payment processing method by either cutting and pasting HTML, or Web code, into the site. Large companies and e-commerce and shopping integration providers can also integrate it as an option within new or existing shopping cart systems

Google Checkout hides credit card numbers and reimburses consumers for unauthorized transactions. It also lets users choose whether to keep their e-mail addresses confidential, and users can opt out of unwanted e-mail from merchants.