100% Defect free vs. Reality.

Is it possible to create 100% bug free software? Theoretically, I suppose it is possible. But then again, how would you know if you've actually acheived it? Design, specs, pre-conditions, post-conditions, unit-testing, test cases, metrics, audits, are all designed to mitigate the introduction of software defects. Unit-testing is designed to break down a problem into managable pieces with test cases that are tailored to that one little bit of code. The idea is that if you have well designed test cases that thoroughly cover a particular domain and all those tests pass, when you begin putting all these pieces together, you run less risk of introducing more defects because each “unit” is solid. This philiosophy is core to XP (Extreme Programming).Read more at http://blogs.borland.com/abauer/archive/2004/09/02/1219.aspx