Files are data on your hard disk (videos, music, pictures, etc.) that can be accessed by PiTiVi and incorporated in your video editing project.
Clips are a visual representation of your files on the timeline. They represent the period of time they consume on the timeline and can be edited independently: each time you drag a file from the media library to the timeline, a new clip is created. As such, a file can be reused as much as you want to create any amount of different clips.
Since PiTiVi is a non-destructive editor, clips are edited, not files. As such, your files stay intact.
You can move a clip within a layer or move it to a different layer.
Click and drag a single clip to move it, and release the mouse button to place it. Dragging horizontally keeps the clip on the same layer, but dragging it vertically moves the clip to a different layer.
To move multiple clips at the same time, use the Ctrl or Shift keys to select multiple clips. Selected clips do not need to be on the same layer. Then, drag the clips just as you would do for a single clip; their position relative to each other will be preserved.
While dragging clips around in the timeline, you can use the following clips (the clips that start after the one you're directly editing) to fill the gap.to move the
Click and drag the clip you want to move, with the mouse button held down
During the drag, hold down Shift on the keyboard
Release the mouse button to end the drag operation, then release the Shift key.
During the drag operation, if you changed your mind and only want to drag one clip at a time, just release the Shift key before you release the mouse button.