Well, the difference between an ArrayList and LinkedList is between the Algorithm used to construct both.
As the name suggests, LinkedList uses 'LinkedList' Algorithm which is Doubly LinkedList. So it every element in it is connected to its previous element and next element which is not the case in ArrayList.
The usage of them is suggested dependending upon the design of ur code. Like Traversal and Addition is faster in the case of ArrayList than LinkedList but Deletion of one element is Faster in case of LinkedList. So depending upon your requirement, you can use them.