Route Groups are a folder convention that let you organize routes by category or team.

Convention

A route group can be created by wrapping a folder's name in parenthesis: (folderName).

This convention indicates the folder is for organizational purposes and should not be included in the route's URL path.

Use cases

• Organizing routes by team, concern, or feature.
• Defining multiple root layouts.
• Opting specific route segments into sharing a layout, while keeping others out.

Caveats

• Full page load: If you navigate between routes that use different root layouts, it'll trigger a full page reload. For example, navigating from /cart that uses app/(shop)/layout.js to /blog that uses app/(marketing)/layout.js. This only applies to multiple root layouts.
• Conflicting paths: Routes in different groups should not resolve to the same URL path. For example, (marketing)/about/page.js and (shop)/about/page.js would both resolve to /about and cause an error.
• Top-level root layout: If you use multiple root layouts without a top-level layout.js file, make sure your home route (/) is defined within one of the route groups, e.g. app/(marketing)/page.js.

Source: docs/01-app/03-api-reference/03-file-conventions/route-groups.mdx