Arrays do not have to be a simple list of keys and values; each location in the array can hold another array. This way, you can create a multi-dimensional array. The reason you may use this type of array is when you have records of each item. For example, car, year, price,... and you want display one record at a time.
In this article principles of using two-dimensional arrays are explained and source code defining two-dimensional array and displaying the array values on the web page is given. More...