When you create a Unity project, Unity creates a folder (named after your project) which contains the following subfolders: Unity also detects when you save new changes to the file and re-imports files as necessary. For many common formats, you can save your source file directly into your project’s Assets folder and Unity can read it. To do this, you can either export the file directly into the Assets folder for your project, or copy it into that folder.
You can bring assets created outside of Unity into your Unity project.
