A component is nothing more than a SketchUp file. If you save a SketchUp file with components in it and then import that into another SketchUp file, that imported file will come in as a component that contains other components. If you right click on the component and choose Save as… you’ll save the component without saving the file it’s in.
You could also save the component via the Components panel by opening the secondary pane and dragging the thumbnail from In Model to the destination folder.
Then when you want to use it, drag it in from the Components panel instead of importing it.