What are the recent technological development in Indian Railways Signalling System? What is track circuitting?

Question

What are the recent technological development in Indian Railways Signalling System? What is track circuitting?

Answer 1

Track circuiting is when an electric current is wired to the rails so that when a train passes over a section of track, it trips a relay which in turn activates an indicator on a track diagram in a signal box. This technology has been around for about a century.

More modern track circuiting also allows for the diagram number of the train (i.e. its code designation in the working timetable) to be shown on the track display, using sensors which read a bar code or similar on the train.