What are examples of 2D and 3D arrays?...

Answer 1

a 2-d array is collection of row and a column
syntax int[][]arr 2d array
three day array eg int[][][] arr;
both are part of multi dimensional array
int[][] arr= {{2,4,5}, {5,6,7}};
2 d array declaration and initialization

Answer 2

Talking about examples:
1. You can see 2D array as matrices. Well, if you dont know matrices enough, then you can imagine them as the SUDOKU puzzles with rows and columns.
2. 3D arrays, ummm...., they can be thought of as a data element storing the dimensions of 3D objects. If it sounds right. :D