logbook

A logbook is a record-keeping book or digital file used to log activities and events in a consistent chronological format. Historically used in navigation and exploration, logbooks have since become standard in transportation, science, industry, and business. A logbook documents times, dates, locations, measurements, and actions taken, providing traceability and accountability. Typical entries include a timestamp, a description of the event, readings or findings, decisions made, and the names of personnel involved. Entries are often signed or authenticated and may reference related documents, equipment, or identifiers.

Different fields have specialized logbooks. A maritime logbook records voyages, weather, course, speed, and incidents; an aviation logbook tracks flight hours, maintenance, and inspections; a laboratory notebook or lab log documents experimental procedures, results, and observations. Maintenance logbooks log service events, part replacements, and calibrations. In many organizations, logbooks serve audit, legal, and safety purposes by preserving an official history of operations.

With digital systems, electronic logbooks are common, offering searchability, timestamps, audit trails, and backups. They may be standalone or part of broader maintenance or compliance software. Regardless of format, good practice emphasizes clear, contemporaneous entries, standardized terminology, and retention consistent with regulatory or organizational policies.