PHP is a scripting language executed on the server side. It is similar to C language and is a commonly used website programming language. PHP's unique syntax mixes C, Java, Perl, and PHP's own syntax. It is conducive to learning and widely used. It is mainly suitable for the field of Web development and has a wide range of applications in the Internet field. This chapter learns the basic syntax of PHP, such as variables, data types of variables, operators, process control structures, etc.