I've been working in a Corporate IT environment for the last 15 years.
Where did I start? It was a hobby for me first of all. Back in the days before the IBM PC came out.
What was the first computer that I owned? It was back in the home micro days:
Sinclair ZX81
Sinclair ZX Spectrum
Amstrad CPC6128
Over the years I've done lots of work on different systems and software packages and worked with lots of different vendors equipment.
IBM
Compaq
Hewlett-Packard
Digital
Programming languages:
C
Assembly code on Z80 from Zilog
C++
Foxpro
Delphi from Borland
Seems that I always go back to C/C++ when I've got some free time.
What do I use now?
Fedora
Postgresql database server
CentOS
FreeBSD
Microsoft Windows