First trained on computers while in the USAF in 1965. Worked on a number of proprietary systems over the years. In the early 80's was trained on my first UNIX system, SunOS on a Sun-2 computer. My first experience with Linux was Slackware summer of 1993(20+ floppies). UNIX systems have included SunOS, Solaris, HPUX, IRIX, Digital, AIX, SCO, BSD, and I'm sure I've missed some. Linux distributions have been many on many architectures. I also have used a number of small Linux releases mainly for routers, including floppyfw, OpenWRT, DD=WRT, Tomato, LEAF Bering-uClibc, and again, I'm sure I forgot some. My latest toy has been a Raspberry Pi which I am currently making into a router for my home network. I'm also planning to test the Pi with wview(weather station collection software) so I won't need a x86 eating a lot of power as this runs 24/7.
Have worked in any number of areas with computers over the years. From repair, to area and regional support positions. Sysadmin, system and network design and implementation and lead engineer for system and network projects.
I have seen a great number of changes over the years. The first systems I worked on had core memory and all transistors, no chips, and used the floor space of a couple of houses. The first disk drive was very much like this one. And yes the heads are hydraulically driven, and a staggering 200 MB of storage. There is more processing power in my cell phone, or Raspberry Pi and many, many times more storage space on the 32 GB flash drive I'm looking at right now.