Main differences between ArrayList and LinkedList data structures are...

Data Structure : An ArrayList is an indexed based dynamic array. A LinkedList is a Doubly Linked List data structure.

Insertion : It is easier to insert new elements in a LinkedList, since there is no need to resize an array. Insertion in ArrayList is O(n), since it may require resizing of array and copying its contents to new array.

Remove elements : LinkedList has better performance in removal of elements than ArrayList.

Memory Usage : LinkedList uses more memory than ArrayList, since it has to maintain links for next and previous nodes as well.

Access : LinkedList is slower in accessing an element, since we have to traverse the list one by one to access the right location.