LESSON 1.1
File-system routing and the app directory
Learn key techniques and workflows in Next.js App Router in Depth.
5m
intermediate
18,240 students
Overview
The App Router maps folders to URL segments and reserved filenames to behaviour. Once you can read a folder tree as a set of routes, most of the framework stops being magic.
In this lesson you will:
- Map folders and page files to URL segments
- Use route groups to organise without affecting the URL
- Recognise the reserved files: page, layout, loading, error, not-found
Pro Tip
A folder in parentheses is a route group: it organises your files without adding a segment to the URL.