What does freeing Nandroid space do?

[rlanza1054]

Hi,

I just installed the latest Clockwork mod on my Nexus 7 and in the Backup/Restore settings there was an option to 'free up Nandroid space'.

What is that space, what is it store?

Thanks

Rob has sent this from his Nexus 7 using Tapatalk 2

 

[NotJustAPhone]

Clockworkmod 6 makes incremental backups, i.e., it only backs up data that has changed since your last backup. Freeing space will delete files that are used only by backups that have been deleted. There's normally no need to select the free space option as CWM automatically frees space everytime you perform a backup.

Sent from my SGS III