After physics laws, here are some programming related laws which you should know---
Lubarsky’s Law of Cybernetic Entomology: There’s always one more bug.

Shaw’s Principle: Build a system that even a fool can use, and only a fool will want to use it.

Woltman’s Law: Never program and drink beer at the same time.

Gallois’ Revelation: If you put tomfoolery into a computer, nothing comes out but tomfoolery. But this tomfoolery, having passed through a very expensive machine, is somehow enobled, and no one dares to criticize it.