Procedural Programming
Procedural Programming is a programming paradigm where a program is structured as a series of step-by-step instructions, using procedures, or functions, and control flow statements like loops, conditionals, and function calls. It focuses on what to do next, in a sequential, top-down manner.
PHP supports functions and global variables needed for procedural programming.
A lot of legacy PHP code is written in a procedural style. It usually evolved to OOP, Object Oriented Programming.