The array taking more than one subscripts is known as multi-dimensional array.

Multidimensional arrays are represented in the form of array of array with each element of the array holding the reference of other array. These are also known as Jagged Arrays.
A multidimensional array is created by appending one set of square brackets ([]) per dimension.

Examples:

int[][] arr = new int[10][20]; //a 2D array 
int[][][] arr = new int[10][20][10]; //a 3D array

MultiDimensionalDemo.java

class MultiDimensionalDemo {
 	public static void main(String[] args) {
  	// declaring and initializing 2D array
  	Int[][] arr = {
   		{
			1,
			2,
			3
	   	},
   		{
			4,
			5,
			6
	   	},
   		{
			7,
			8,
			9
   		}
  	};

  	// printing 2D array
  	for (int i = 0; i < 3; i++) {
   		for (int j = 0; j < 3; j++)
			System.out.print(arr[i][j] + " ");

   			System.out.println();
  		}
 	}
}