Let's talk about the HP-9000 as depicted in http://www.typewritten.org/Media/Images/hpwindows-starbase-u...
There is a `man` entry displayed in a terminal window there. The first Unix I've ever touched was HP-UX on an HP-9000 (server series, not the workstation one), and I have this memory that the underlined words you can see in that manpage as well were actually hyperlinks you can select and would bring you to the relevant section of the manpage that discussed that term. Am I fabricating that memory or is it real? I cannot find any info about it on the Internet.
I started with HP-UX 9.03 on a PA-RISC-powered 715-75 (to use Emacs, our whole research group logged into the 735 server to edit there, which was faster than running it locally).
Any unclean pointer fiddling in C, and the process was terminated by the OS, so the machine was wonderful to use as a development box (especially with Purify installed) for software that would later be run on Windows or Linux.
I eventually bought my own refurbished (and using academic discount) 715 (instead of a car), so I had the fastest machine in our student dorm of anyone I knew, undergrad, grad student or professor. I could just write my Master's thesis when everyone else kept re-installing Windows - the HP never crashed in 6.5 years, which has left me with deep respect for the old-schol (pre-Compaq) HP engineers. The machine (21" color CRT) occupied half of my 9 square metre dorm room, but it also kept me warm.
I thought only `info` had hyperlinks
In the GNU world, indeed. And that's why it makes even harder for me to remember exactly, it was 30 years ago, I was clueless and also Linux was already "big enough" to have some Red Hat installed in some x86 PC in the same lab.
My 'first Unix' was MIPS Risc/OS, and it had that feature too.