Signalling system

Railway signalling is a system used to control railway traffic safely, essentially to prevent trains from colliding. The main purpose of signalling is to maintain a safe distance at all times between all trains on the running lines. The secondary aim - particularly today - is to make the best use possible of the railway infrastructure, so that the total throughput of trains meets business requirements. There are 'fixed block signalling systems' and the more modern 'moving block signalling systems', which increases line capacity.