I design and develop software for the electronic design automation industry. Such software is used by any company that designs electronics, like Intel, Sony or GM.
I specialize in the design analysis side, the software that hardware designers use to describe their designs at a relatively high level in a language like Verilog, SystemVerilog, VHDL or SystemC, then analyze and debug using simulation, timing analysis, power analysis, rules checking, etc.
It takes large teams of developers to write and maintain the software tools used by hardware designers. While there are a number of notable exceptions, most design automation software is used on Unix/Linux machines rather than PCs or Macs.
--Percy