Guys - to explain a little further - it goes something like this ...
Fulls, Incrementals and Differentials are part of your backup strategy.
Full - Backs up everything, takes longest, takes more space ... are the basis of any full restore.
(lets say you take a Full every Saturday).
Incremental - Only backs up files changed since the last backup (be it Full, Incremental or Differential), fastest, takes least space.
(let's say you take an Incremental every day from Sunday to Friday (instead of Differentials): S-I, M-I, T-I, W-I, T-I, F-I, S-F)
- quickest to restore in a partial restore (to recover files to a particular day of that week)
- slowest to restore in a full restore (as you have to restore the last Full and every Incremtental on top)
Differential - Seeks a middle ground as cumulative back ups of files changed since the last Full backup, mid-fast speed, low-mid space (getting larger as the week goes on).
(let's say you take a Differential every day from Sunday to Friday (instead of Incrementals): S-D, M-D, T-D, W-D, T-D, F-D, S-F)
- slightly slower to restore in a partial restore (to recover files to a particular day of that week)
- faster to restore in a full restore (because you only ever need 2 backups - the Full and the last differential (of the day you want to restore to)).
Or you could do a Full Saturday, Differential mid-week and Incrementals every other day: S-I, M-I, T-I, W-D, T-I, F-I, S-F