I will site a list here about what every PHP Developers should know.
- Comments should not be taken for granted. Insert comments and explain the purpose of the code, the next developer should find this very helpful
- Recycle functions. Check first in the PHP website if by any chance the function you want is already existing, this will save you the time and let the job done.
- Study the best practices in coding or the standard way of coding in PHP. So the next developer will not get a headache in tracing or debugging your work
- As the saying goes, "There's more than one way to skin a cat.", this is also true in programming there are more than one way to create a solution but, there is always the best solution.