A Handy Tool
Software: Apple FCP X
One of the handiest keyboard shortcuts for Final Cut Pro X is Shift + Z .
Typing Shift + Z in the Timeline scales your entire project to fit in the Timeline window. This only changes the display of your clips. It does not change the duration of any clip or project.
Typing Shift + Z in the Viewer scales the entire image to fit in the Viewer. This only changes the display of the image, not the scale of the image in your project.
Typing Shift + Z in the Browser changes the display of clip thumbnails so that you only see one thumbnail per clip.