Ship’s Log
From French bitacle, the word binnacle has two very specific uses. On the one hand, the term binnacle is used to designate the wooden box, referred to as locker, it may be cylindrical or prismatic in shape, and which is fixed to the deck of the ship, next to the rudder wheel and on which the nautical needle is mounted with the clear purpose of keeping it horizontal; in spite of the common rocking and swaying the ship in question may incur. All binnacles are fitted with magnets and on the outside with spheres of soft iron, which will have the function of annulling the disturbing effects of the iron on board and; on the other hand, the magnetic field surrounding the needle become uniform, indicating magnetic north at all times. Way back in time, when it came to ships that did not have a covered pilothouse, a ship’s log with instructions was kept inside the binnacle to protect it from extreme weather that could hit the ship; as a result, from this it follows the origin of the other use of the term.
A written record of the actions, tasks or activities to be carried out in a given activity, enterprise or job is also called a logbook. It will include the imponderables that developed during its fulfilment, the failures, the costs and the changes that had to be made, in order to achieve the objectives. Nowadays, both students and workers in areas such as design usually carry with them a logbook, in which they carry out and which, clearly, is fundamental to it.  
Source: ABC and RAE