An array with two dimensions is called as a two-dimensional array. It is also called as a matrix. In C, a two dimensional array is initialized as int arr[nb_of_rows] [nb_of_columns]. Hence, two dimensional arrays can be considered as a grid. An element in a two dimensional can be accessed by mentioning its row and column. If the array has 20 integer values, it will occupy 80 bytes in memory (assuming 4 bytes for an integer). All of the bytes are in consecutive memory locations, the first row occupying the first 20 bytes, the second the next 20, and so on.