PHP: Hypertext Preprocessor (PHP) is a server-side scripting language frequently used as part of web development and as a command-line tool for common tasks.
One of the great strengths of PHP is in its associative arrays functionality.
In programming terminology, a traditional array is a sequence of values that can be accessed using their index value. Using brackets, the index of an entry can be used to access its value.
In PHP, arrays can also be associative arrays. Instead of an index value, the array can be series of key-value pairs where string values can be used as the index. (This is also sometimes called a map where one set of values are mapped to others.)
Instead of using brackets to define a sequence of values, the function array() can be used to create associative arrays. Using the name of one of the keys (“Dan” in this example) is linked to the value associated with it (value of 33).
Indexed Arrays are Associative Arrays
Internally, indexed arrays are associative arrays where its key is a number. Using the function var_dump() shows this.
Like many other programming languages, arrays can also be multidimensional. Associative arrays can be inside associative arrays can be inside associative arrays.