> For the complete documentation index, see [llms.txt](https://docs.digitalriver.com/commerce-api-references/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart.md).

# Cart

- [Apply a shopper to a cart](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/apply-a-shopper-to-a-cart.md)
- [Line items](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/line-items.md)
- [Billing address](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/billing-address.md)
- [Shipping address](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/shipping-address.md)
- [Payment methods](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/payment-methods.md)
- [Shipping options](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/shipping-options.md)
- [Web checkout](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/web-checkout.md)
- [Submit a cart](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/submit-a-cart.md)
- [Apply or detach payment methods](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/apply-or-detach-payment-methods.md)
- [Apply a shipping option](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/apply-a-shipping-option.md)
- [Carts](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/carts.md)
- [Cart offers](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/cart-offers.md)
- [API trigger offer](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/api-trigger-offer.md)
- [Resume cart](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/resume-cart.md)
- [Third-party subscription engine](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/third-party-subscription-engine.md)
- [Tax registration](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/tax-registration.md)
- [Price override](https://docs.digitalriver.com/commerce-api-references/shopper-apis/cart/price-override.md)