Use of array: All the elements are lumped together in one 
block of memory. Individual elements can be accessed thru 
Array index. Random access & Dynamic allocation are 
possible.

Use of Linked list: Linked list allocates space for each 
element separately in its own block of memory called 
a "linked list element" or "node". It gets the overall 
structure by using pointers to connect all its nodes 
together like the links in a chain. Here the elements of 
list can be accessed thru memory address (Since the pointer 
stores a reference to another variable)which improves the 
efficiency. Size of the list can also be modified (ie) we 
can insert/delete elements of the list.