Solution

Concept:

Using a transaction log, or journal, journaling improves the filesystem's dependability and enables rapid crash recovery. The journal is an on-disk log of metadata, or data about the filesystem, which is kept current as the filesystem is modified. Without journaling, filesystems save changes to updates in memory.

Explanation:

A journal means a record that is kept over time, like a diary. Instead of changing the structure of the file system, adding new directories, or making files bigger, the first thing the file system does is collect these changes into a series of transactions and add them to a log file. Then, these transactions can be sent to the actual file system by processes that run in the background. If there is a crash, the file system can recover immediately and start committing transactions already in the journal. However, the last entry will probably be corrupt and will be dropped. All of these things mean that the file system won't change. This kind of file system, like ZFS, will help protect both data and metadata, and it won't need programs like fsck that try to fix broken files.

Hence, File saving as transaction is called Journaling in Linux operating system.