What is a characteristic of block signals?

A characteristic of block signals is that they regulate train spacing on tracks. Block signals play a crucial role in maintaining safe distances between trains. They do this by controlling the movement of trains through designated sections of track, or "blocks." When a block signal is indicating that a block is occupied, it prevents the following train from entering that block until it is safe to do so. This function is essential for avoiding collisions and ensuring that trains can operate efficiently and safely.

In contrast, while signals may indicate speed limits, that is not their primary purpose; their main focus remains on controlling track occupancy rather than speed regulation. Similarly, while some signals may be associated with crossings, this is not a defining feature of block signals specifically, as their primary function is related to sections of track rather than points of intersection with roadways. Finally, block signals do not define the end of a railway line; rather, they manage the movement of trains within the operating area of the railway network.