Journal

1. Location of stored activities or events occurring to a computer and/or network. A journal helps to determine what may have caused an issue or a device to go down without having to constantly manually monitor a device. 
2. When referring to a file system, journaling is a method of keeping track of how the data is manipulated on the hard disk drive. Each time a request is made for something to be manipulated on the hard disk drive, an entry is first made in the journal. This enables the system to only have to check the last few journal entries for errors instead of having to check all the files on the drive for any errors if the system crashes or reboots. For example, Windows 98 running FAT32 is not a journaling file system and this is why the system must run scandisk if the computer is improperly turned off. However, Windows XP running NTFS, which is a journaling file system, does not need to run scandisk, it simply checks the journal.

Also see: File system, Log, Operating system definitions, Weblog