A differential backup backs up only transaction logs, but does not clear them. If you perform a full backup and then perform only differential backups, the last full backup plus the latest differential backup has all data needed to bring the database back to the most recent state. This type of backup is also called a cumulative incremental backup.
Differential backup allows users to copy files created or changed since the last full or incremental backup. It does not mark files as having been backed up. If you are performing a combination of full and differential backups...
a backup done only of what have changed since a previous backup (the "backup of reference")
a backup in which
a copy of only the changes since the last full backup
a copy of only those files that have changed since the last full backup (plus new files that were created more recently than that, of course)
a cumulative backup of all changes made since the last full backup
a partial copy of a database onto a backup device
It is a backup type that retrieves new or modified files from a client machine since the last total backup
Every file that has changed since the last full backup is backed up. It is faster to restore a differential backup. All you need is the last full and last differential backup.
Backup that copies only the files that have changed since the last full backup. 12.20
A backup that copies files created or changed since the last normal or incremental backup. It does not mark files as having been backed up (in other words, the archive attribute is not cleared). If you are performing a combination of normal and differential backups, restoring files and folders requires that you have the last normal as well as the last differential backup. See also: copy backup; daily backup; incremental backup; normal backup