I remember learning everything there is to know about Quark Xpress in college, then when I graduated I was so pissed when I found out that everyone wanted InDesign users instead.
Problem was that Quark had everything built that needed to be built in the early 90s. You could slam CMYK publication documents that supported Postscript and Truetype fonts and text boxes with picture runaround linked to multiple pages directly to imagesetters when every other application was working on designing a GUI. They were done. Kinda like designing the wheel. What do we do now? Adobe then stole the acronym PDF (used to be defined as "printer description file") and reinvented the layout and imaging paradigm. (There was no PDF format back then really) For page layout, there was really nothing better. Those XTensions, (third party plugins) were the coolest. In those days you could even customize error messages that would pop up in Quark with ResEdit. Especially the dumb ones. In Quark, if you didn't have the correct font loaded when opening the file, it would say something like "The font "XXxx" is not available, would you like to reformat the document and use the system default font?" We changed the OK popup to read "Go Ahead and Destroy my Document" Lots of fun to be had in those days with new employees!