The Name
The name consists of two parts—"PHP" and "BB". PHP is the programming language in which the software is written, and "BB" stands for "bulletin board"; it’s a bulletin board tool written in the PHP programming language.
PHP itself is an abbreviation, and it stands, or at least used to stand, for Personal Home Page. PHP is no longer just a set of personal home page tools as it was in the beginning, but has grown to become a true programming language. Its abbreviation has gone one level deeper, and now recursively stands for "PHP Hypertext Preprocessor". But it’s really known simply as PHP.