A reserved track is like a special road that only certain people or things can use. Just like how some roads are only for cars and others are only for bikes, a reserved track is a special path set aside for a particular purpose.
For example, some train tracks have sections that are reserved for certain trains or cargo. This means that only those special trains or cargo can use that part of the track, and other trains have to wait or use a different track.
Think of a reserved track like a VIP section at a concert. Only a select few are allowed in that area, and everyone else has to stay in the regular sections. It's a way to make sure important things or people have their own space and can move smoothly without any obstacles.