Originally Posted by
Capot
Total dependence on computers, 4 parallel systems for safety; hmmmmm....
x4
...
From a Software Engineer's perspective, your worry is pretty far from the reality. The relationship between the computer systems in aircraft flight control compared to the computers we interact with in a home or business sense is somewhat akin to the relationship between an old pick-up truck or marine diesel engine versus the engines used in Formula 1.
By which I mean that the former are designed to plod along doing their thing until doomsday without anything going wrong, whereas the latter are tuned for performance with the expectation that they will crash occasionally. There is no complex operating system involved in flight control logic, and the software has been exhaustively tested - it won't necessarily be perfect, but it won't do anything in and of itself to put the aircraft in danger.
Most of the previous posts are correct - digital FBW is implemented in the Airbus models of the A320, A330/A340 and A380 series, as well as the Boeing B777 and B787. Analogue FBW was implemented in Concorde.
Fundamentally, FBW means that the connection between the flight controls and the flight surfaces is electronic rather than electro-mechanical - that's about it.