Why is Railway Signals Important?

Railway signals control the movement of trains. They help to keep the train away from each other to avoid collisions and also keep them running efficiently and on time.

The block is the basis of a signaling system. It is a stretch of line in one direction. No more than one train can be in a block at a time. A stop signal controls entry into the block. It it is red, the driver has to stop there.

A distant signal before the start of a block warns the driver of what the stop signal will show, so if necessary he can start to slow down.

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How Many Type of Keys on a Keyboard?

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