To be honest, making a back-up on a regular basis is a good idea, regardless if there is a new iOS to upgrade to.
So yes, I would say you need a backup just because you never know what matter happen. Computers do mess up.
There are two way to make a backup - via iTunes and using iCloud.
To make a backup in iTunes, connect the iPad to the iTunes the iPad was initially synced with. Then, select the Backup prompt and let iTunes do its "magic." By the way, this is a more comprehensive backup.
To make a backup via iCloud, you do not need iTunes (or a computer for that matter). On your iPad, navigate to the iCloud line in your Settings app. If backup is off, turn it on and then allow iCloud to make a backup.
Again, may I suggest you make a backup often, just in case. It's safest, IMHO.
Marilyn