Tracks can be dragged to any position within the document. Unlike using cut and paste, dragging a playing track doesn't interrupt its audio.
To drag a single track, left-click on the track's name, and while holding down the left mouse button, position the cursor wherever you want the track to go.
To drag multiple tracks, select the tracks, left-click one of their names (it doesn't matter which one), and while holding down the left mouse button, position the cursor wherever you want the tracks to go.
When you release the left mouse button, the dragged track(s) are inserted before the track that's under the cursor. If you change your mind during the drag, press Esc to cancel the move.