Select File > Save Scene (Ctrl+S).
The first time you save the scene, you are prompted to give it a location and filename.
Save your scene as a compressed archive file
For easier file system maintenance and backup, you can save the scene file and its associated companion folder into one compressed archive file.
Save your scene with associated textures
To easily share complex files with many textures, you can save the scene file and its textures into an associated companion folder.
All image textures used in the scene are copied to the companion folder for the file.