During my youth —throughout middle school, high school, and college —I used quite a various number of PC platforms:

• Zenith Z-100
  I was in high-school, 1986, at SUNY Potsdam, when our neighboring Clarkson University (required/issued) the Z100 desktops to all incoming freshmen).  I spent many days working with students, understanding the computer, solving problems, etc..

• IBM PS/2 Systems
  This was the system, that I used in High School that I cut my teeth on BASIC, Turbo Pascal, and Turbo C.

• PC Clones (very popular in college)
  In college, we upgraded to Turbo C++, along with machine language (assembler), and various other platforms.  

I carried around a Apple PowerBook 170 and did a lot of my Pascal programming and other assignments on that system.  However, in many of my CIS classes we used the PC clones to do our work,  all running MS-DOS initially connected with Novell networking (w/ BNC coxial), and later twisted-pair.  I wrote some TSR (terminate and stay-ready) programs like a clock and system performance displays (CPU, RAM, IRQ status, etc..).   Wrote a multi-person network based tic-tack-toe game, after writing our own network packet drivers, and dabbled in some preliminary operating-system development.