Log data consists of files that are records of events, transactions, or messages:
Event logs—record actions that take place at a specific time (timestamp) that can be used to understand user behavior, application and system activity, or to diagnose problems.
Transaction logs—record changes to stored data that allow you to recover the database from crashes or other data errors.
Message logs—record (i.e. save) textual communication, both public (IRC channel/IM conference/MMO public/party chat messages) and private messages between users.
Logging with intent