Software is Increasingly Complex. That Can Be Dangerous. The Apollo 11 moonshot was done with about 145,000 lines of code and a lot less computing power than your printer. Today’s Microsoft Windows contains some 50 million lines of code. A Boeing 787 runs on 7 million lines of code, but a modern car actually runs on 10-100 million lines of code. Google’s infrastructure is estimated to have 2 billion lines of code. It takes an army of programmers to build and maintain these systems, but it is increasingly harder to code and test every permutation of what machines and users might do.

https://www.extremetech.com/computing/259977-software-increasingly-complex-thats-dangerous