I've been a developer for over 30 years in one form or another. I learnt Pascal at University and my first job was programming in Fortran 66. I've since moved to C# & .NET via Ada, C and C++.
Over the years I've used most operating systems (apart from MacOS), starting with PR1MOS and then moving onto various flavours of Unix. I'm now exclusively on Windows (until a job that requires Unix comes along!).