What belongs in a ship's library?

What books should be carried in a ship's library?

Useful technical and survival references should sit alongside recreational books, with the mix changing by period and crew literacy.

A useful ship's library needs technical books on seamanship, wreck survival, and firefighting. A modern ship should also carry mechanical and electrical engineering references for problems that arise away from shore support. Recreational reading matters because boredom and morale are practical shipboard concerns rather than luxuries. In the age of sail, a captain's or officers' collection differed from a modern crew library because much of the crew could not read.