Technical support writing is kind of technical writing
But I want to know what is mean and if there an example?

Pick up any software manual or how to computer book.

It's basically the documentation of anything technical

No it not helped
I want to know what is means with any example?
Also user guide and online help if you have any idea about it?

Here's an example of a manual from a Dell site:

Documentation (http://docs.us.dell.com/support/edocs/systems/ins8500/en/8600cr/sm/upgrades.htm)

Thank yooooou wondergirl
It really helpful