Note: If you edit in Prefab Mode, saving through File > Save only saves changes to the open Prefab. Exit the Prefab Mode to save wider changes.
Unity saves some information automatically while you work in the Editor. See Automatic saves for more details.
Scene changes include modifications to GameObjectsThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary in the SceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary. For example:
Project-wide changes in Unity apply to your entire project rather than a specific scene. For example, if you create a temporary scene to test changes, you can save the project and not the scene.
Project-wide changes include:
Project SettingsA broad collection of settings which allow you to configure how Physics, Audio, Networking, Graphics, Input and many other areas of your project behave. More info
See in Glossary: When you save your project, Unity saves changes to the Project Settings in the
Library folder, in these files:
Build Settings: Unity saves changes to the Build Settings in the
Library folder as
Changed assets: When you save project-wide settings, Unity saves any unsaved assets.
Note: Some asset types have an Apply button in the Inspector. Unity will not save these unless you select Apply.
Dirty assets: Unity saves Dirty assets, which are files on your disk that are modified in the software but not saved yet. You can use custom Editors and scriptsA piece of code that allows you to create your own Components, trigger game events, modify Component properties over time and respond to user input in any way you like. More info
See in Glossary to mark an Asset as dirty in one of these ways:
Unity automatically saves the following changes to your disk: