Q. What is a 'block hut' or 'block post'?
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A block hut or block post is a minor station (usually Class C; see section on stations) on a section with light traffic, which does not have the full complement of home and starter signals to control the reception and departure of trains. It often has just a single stop signal, and a permissive signal (a distant) to its rear. Line Clear is not granted to a train until the whole of the last preceding train is known to have passed (complete --...
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without parting) at least 400m beyond the home signal and is known to be continuing its journey. An intermediate block post is a Class C station similar to a block hut on a double line, however in this the signal corresponding to the block post is actually controlled by the signal cabin at the station to the rear, and the intermediate block post is not manned at all. See intermediate block section. The terminology 'Block Hut' in contrast to a block post is often taken to imply that the station or halt is manned.
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E.g., on the Howrah - New Delhi line, the Dhanbad - Mughalsarai section (especially around Gurpa - Gujhandi) has many block huts, in some cases with practically every other station or halt being a block hut.
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Source: IRFCA