What is the difference between array_walk and array_map in PHP?

Array_walk and array_map are both array processing functions in PHP, but they have some differences in their usage and functionality.

The array_walk function is used to iterate through each element of an array and apply a user-defined callback function to it. The callback function can modify the values of the array, but it does not return a new array.

The array_map function is used to apply a user-defined callback function to each element of an array and return a new array containing the return values of the callback function.

In summary, array_walk is used to iterate through an array and make modifications to it, while array_map is used to apply a callback function to each element of an array and return a new array.