How to Sort an array without using any predefined method/activity (Invoke method, Array. Sort(arr))

How to Sort an array without using any predefined method/activity (Invoke method, Array. Sort(arr)).

Hi

Array.Sort(arr) is the fastest method and the optimal one

May I know the reason why we need another way
Any specific reason

Cheers @Surabhi_Basal

@Surabhi_Basal