A much scaled down description of just one of his duties which is tracking the movement of various trains in his section is as follows:
Fig 1 - Screen Shot of Signaling Layout Display in Control Room
In this screen shot of part of an interlocking (Fig 1), unoccupied tracks are in grey, tracks occupied by trains are in red. Each track circuit is given a unique number, as are signals and points. Points are numbered in pairs (in yellow) where there is a crossover and they must operate together. Point numbers are provided with letters A or B to denote the ends of the crossover. Train 7752 (its ID, or "description", being displayed in a black box) is standing in the platform of Oak station on track circuit 107 awaiting permission to proceed. Signal C23 is showing a red aspect because no route has been selected and locked. The black square next to the red of C23 is the indication for shunt signal C25 covering the route into the siding. Overlaps are indicated in modern installations by a mark at the end of the track circuit concerned.