<ul> <li \>Classes must be named by following the naming conventions. </ul> <ul> <li \>The brace is always written right after the class name (or interface declaration). </ul> <ul> <li \>Every class must have a documentation block that conforms to the PHPDocumentor standard. </ul> <ul> <li \>Any code within a class must be indented four spaces. </ul> <ul> <li \>Only one class is permitted per PHP file. </ul> <ul> <li \>Placing additional code in a class file is NOT permitted. </ul> This is an example of an acceptable class declaration: