An associative array is a data structure that stores data in key-value pairs. Unlike traditional arrays that use numeric indices, associative arrays allow you to use strings or other types as keys. This makes it easier to access and manage data, as you can refer to values using meaningful names instead of numbers. In many programming languages, such as JavaScript, Python, and PHP, associative arrays are commonly used. They enable developers to create more readable and maintainable code by allowing direct access to values through their associated keys, enhancing the overall efficiency of data handling.