The reason I ask is I've had my Win 8 machine offline for a little over three years and may soon get DSL and reconnect and want to be prepared for what might happen when Microsoft sees my machine again. Terabytes of updates? BSoD?
If you're running Win8 (as opposed to Win8.1), I encourage you to update at least to 8.1. There are a lot of improvements between 8 and 8.1.
If you're already running 8.1, you have support for quite a few more years. Yes, you'll be "encouraged" to upgrade to Win10, but you don't necessarily have to. Heck, I'm running Win7 on almost all my Windows boxes, and don't plan to take them to Win10 any time soon.
I have a Windows 7 laptop that I had not used or updated for over a year...I recently turned it on and got updates over several days IIRC. No problems...All worked fine. It took longer than usual of course.
I keep it for backup just in case. Put all my files and photos on a flash drive and updated those, too.
There were no annoying notices asking me to get Windows 10.
My newer laptop came with 10.
Read this and it will explain how to prevent the automatic upgrade to Windows 10.
It’s easy to do.