Installing Operating Systems - CompTIA A+ 220-1002 Prof Messer

I'm a little confused about why you would need a partitioning for anything other than system recovery. I understand the theory behind doing it but not why you would want to.

Partitioning does a few things. It makes a single device (like a hard drive) appear like more than one. You can use this to be able to access multiple file systems, for one thing. On Windows this isn't as big as really there is just FAT32, NTFS, and ReFS. But on Linux there are dozens of reasonable ones and we use partitioning for that all of the time.

Another is risk domains. You might have something that likes to fill up a disk quickly and you won't to isolate it from other parts of the system. that way if it fills up it doesn't kill the OS or the database. Popular for log directories.

You might want to forcibly keep users from using too much space for personal files, so you limit it via a partition size. Uncommon, but possible.

You often take backups at the partition level. So it is very common to put critical data on an individual partition so that an image based tool like Veeam can backup what is critical differently than stuff that is less critical.

Snapshots are normally at the partition level as well, so multiple partitions means you get snapshot flexibility and performance benefits.

Very interesting, specially the Scott's reply.