MyBB Community Forums

Are there any tutorials about the basic of coding?What program language should i know so i can make plugins and modifications?

PHP, MySQL, and HTML.

There are lots of tutorials on PHP on the net. I think there was some tutorials over at mybbcentral.com. But your best bet for information is php.net. The official site has tons of documentation on all the functions you will need. Check there before you decide to write a function to sort an array or such.
I wrote a function to wordwrap until I found out PHP had one built in

Thank you very much!