Declaring

Let's declare a 2D array with 3 rows and 5 columns

int[][] exampleArr;

This 2D array is only declared, and doesn't have any data. Let's put some in it!

Initializing

// Use this type of initialization when yo plan on filling it later procedually (like in a loop)
int[][] exampleArr = new int[5][3]; //Sets all data to an int of zero

// Use this if you want data to give to your program that you don't need to calculate
int[][] exampleArr = 
{
    {1,2,3},
    {3,6,9},
    {9,18,27}
};

In Java, there are two ways to create arrays.

Just note that it usually is easier to use the first way for objects you created.

Now let's acutally use these arrays!