In PHP, variables are used to store data that can be reused throughout a script. A variable in PHP starts with a $ symbol followed by the variable name (e.g., $name). PHP is a loosely typed language, meaning you don’t need to declare data types explicitly. PHP supports several data types, including strings, integers, floats (doubles), booleans, arrays, objects, NULL, and resources. Understanding PHP variables and data types is essential for handling data, performing operations, and building dynamic web applications. This foundational knowledge helps developers manage content, user input, and logic effectively in any PHP-based project.