.next/

The .next/ folder is where Next.js builds your application. It is usually hidden from view in your editor.

What's inside?

This folder is common to all Next.js projects and is where Next.js stores the following:

• Pages - Each page in your project is compiled into a .html file in this folder.
• Static files - Static files like robots.txt are placed in this folder.
• Serverless Functions - Serverless Functions are compiled into .js files in this folder.
• Build Manifest - The build manifest is an internal Next.js file that maps pages to static files.
• Cache - The cache folder is used for speeding up builds.
• Other build files - Other build files are also placed in this folder.

You can read more about the .next/ folder in the Next.js documentation.