If why we use 2d array to store data even we can store it in 1d array?

Question

We can store data in both int a[1][2] and int a[2] so why 2d?

Answer 1

It is useful if you want to compute data in tabular form and useful in performing operations related to matrices

Answer 2

For example, it would be somewhat difficult to display the points with Cartesian coordinates in a simple array.