Your theme controls how your online store looks and what it shows on each page: the layout, the sections and blocks, the colors and fonts, the header, the footer, the product pages and the cart. Shopify controls how your store sells: checkout, payments, prices, taxes, shipping and the emails customers get. Apps control their own features.
Reviews, wishlists, chat, popups and other app features
The app
The app's own settings, and its block in the theme editor
Parts that the theme and Shopify share
Some parts of a page come from Shopify, and the theme only decides where they show and how they look.
Prices. Shopify sets the price and converts it to the customer's currency. The theme decides where the price sits and how large it is.
Tax and shipping notes. Under the cart subtotal, the theme shows one line when your prices include tax and another when they don't. Whether prices include tax is a Shopify setting. The wording of the line is theme text that you can change.
Sold out. Shopify decides whether a product can be bought by the customer who is looking at it. The theme shows Sold out when it can't. All my products show as sold out lists the Shopify settings behind it.
The Powered by Shopify line in the footer. Shopify writes the link, and the theme places it. Remove the Powered by Shopify link shows how to hide it.
Checkout and customer accounts
Checkout has its own editor, separate from the theme editor. To set the logo and colors of checkout and the customer account pages, go to Settings > Checkout in your Shopify admin and edit a configuration. Shopify's guide to the checkout and accounts editor has the steps.
Apps
An app that adds something to your storefront is built and supported by its developer. An app can add a block that you place in the theme editor, or an app embed that you turn on there. If the app's feature shows wrong data or does not work, contact the app's developer. If the block does not show at all, check that you added it in the theme editor and saved.
When you still can't tell
Look at where the problem appears. The pages a customer sees before they click the checkout button come from your theme, the cart included. Checkout, the thank you page and the order emails come from Shopify. If the problem is in your theme, contact support.
Your theme controls how your online store looks and what it shows on each page: the layout, the sections and blocks, the colors and fonts, the header, the footer, the product pages and the cart. Shopify controls how your store sells: checkout, payments, prices, taxes, shipping and the emails customers get. Apps control their own features.
Where each part is set
Part of your store
Set in
Where to change it
Page layout, sections, colors, fonts, header, footer, cart
Your theme
The theme editor (Online Store > Edit theme)
Fixed text on the storefront, such as Add to cart
Your theme
Edit default theme content, as in Change the wording on your store
Checkout pages, thank you page and order status page
Shopify
Settings > Checkout, in the checkout and accounts editor (Shopify Help)
Order confirmation and shipping emails
Shopify
Settings > Notifications (Shopify Help)
Tax rates, and whether prices include tax
Shopify
Settings > Taxes and duties (Shopify Help)
Shipping rates and the countries you ship to
Shopify
Settings > Shipping and delivery (Shopify Help)
Prices in other currencies and exchange rates
Shopify
Markets (Shopify Help)
Customer account pages, such as orders and addresses
Shopify
The checkout and accounts editor (Shopify Help)
Payment methods
Shopify
Settings > Payments (Shopify Help)
Reviews, wishlists, chat, popups and other app features
The app
The app's own settings, and its block in the theme editor
Parts that the theme and Shopify share
Some parts of a page come from Shopify, and the theme only decides where they show and how they look.
Prices. Shopify sets the price and converts it to the customer's currency. The theme decides where the price sits and how large it is.
Tax and shipping notes. Under the cart subtotal, the theme shows one line when your prices include tax and another when they don't. Whether prices include tax is a Shopify setting. The wording of the line is theme text that you can change.
Sold out. Shopify decides whether a product can be bought by the customer who is looking at it. The theme shows Sold out when it can't. All my products show as sold out lists the Shopify settings behind it.
The Powered by Shopify line in the footer. Shopify writes the link, and the theme places it. Remove the Powered by Shopify link shows how to hide it.
Checkout and customer accounts
Checkout has its own editor, separate from the theme editor. To set the logo and colors of checkout and the customer account pages, go to Settings > Checkout in your Shopify admin and edit a configuration. Shopify's guide to the checkout and accounts editor has the steps.
Apps
An app that adds something to your storefront is built and supported by its developer. An app can add a block that you place in the theme editor, or an app embed that you turn on there. If the app's feature shows wrong data or does not work, contact the app's developer. If the block does not show at all, check that you added it in the theme editor and saved.
When you still can't tell
Look at where the problem appears. The pages a customer sees before they click the checkout button come from your theme, the cart included. Checkout, the thank you page and the order emails come from Shopify. If the problem is in your theme, contact support.
Related tasks:
Change the wording on your store
Translate your store
My changes don't show on my store