Shop Pay is an online checkout service offered by Shopify that allows customers to store their credit card, email, shipping, and billing information and then use it to make purchases online. It is a fast, flexible, and secure one-tap checkout option that can save customers time when they check out. Shop Pay also offers a "buy now, pay later" option called Shop Pay Installments, which is a service from Shop Pay and Affirm, a third-party provider that lets merchants get paid when an order is placed while letting customers pay over time.

Some key features of Shop Pay include:

• Fast checkout: Shop Pay is the fastest one-tap checkout for secure payments online, on social media, and on the Shop app.
• Secure payment: Shop Pay is a secure payment option that allows customers to lock in their personal information and unlock carefree, one-tap checkouts everywhere they push purple.
• Carbon removal program: Every Shop Pay purchase supports carbon removal projects at no extra cost.

To use Shop Pay, customers need to activate it from the Shopify admin by going to Settings > Payments and checking Shop Pay. Customers can also change their Shop Pay account information and opt-out of Shop Pay at any time. Shop Pay is best suited for business owners who do most or all of their business online since most of its unique features are primarily relevant to online sales.