When you put any asset into your Assets folder, it appears in your Project window. Unity automatically detects files as they are added to the Assets folder, or if they are modified. If you delete them within the Unity Editor Project window, you also delete them from your computer. Warning: In most cases, the items that appear in your Project window represent actual files on your computer.

If you modify the import settings for an asset, or make a change to the source file in the Assets folder, Unity re-imports the asset again to reflect your changes. Instead, the import process reads your source file, and creates a game-ready representation of your asset internally, matching your chosen import settings. When you modify a file in Unity, Unity does not modify your original source file, even though you can often choose between various ways to compress, modify, or otherwise process the asset within Unity. Therefore, if you save or copy a file to your Assets folder, Unity imports it and appears in your Project window. You can save or copy files that you want to use in your project into the Assets folder, and you can use the Project window A window that shows the contents of your Assets folder (Project tab) More info See in Glossary inside Unity to view the contents of your Assets folder. 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.

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