What is a linux-suspend partition
 

The title is fairly self-explanatory, but I'll give details so this is a proper thread. ;)

A little while ago I deleted my Ubuntu partition in a fit of frustration. Now I'd like to restore it, but all that's left is something labeled "linux-suspend". (sda5) It would be good to know, for future reference, how to uninstall Ubuntu properly.

You don't "uninstall" an operating system, you simply replace it with something else.

That partition is where all of the data in RAM gets dumped when you suspend your machine, so it can later be pulled back out of that partition into RAM when you resume.

So that means there's nothing left of the installation at all?

It depends on what you did after you deleted the partition. If you left the space free, you MAY be able to recover the partition with a disk recovery tool. If you reallocated the space, assigned another partition, wrote anything to it, etc. then it's gone. You might be able to recover individual files by using a disk recovery tool, but it'll take some work.

If there was nothing on that partition that you need, you'd be far better off just reinstalling.

It'll probably be easier just to reinstall.