We use shallow copy
when a new instance type gets created. It keeps the values that are
copied in the new instance. Just like it copies the values, the shallow copy also copies the reference pointers. Reference points copied in the shallow copy reference to the original objects. Any changes made in any member of the class affects the original copy of the same. Shallow copy enables faster execution of the program.
Deep copy is used for storing values that are already copied. Unlike shallow copy, it doesn’t copy the reference pointers to the objects. Deep copy makes the reference to an object in addition to storing the new object that is pointed by some other object.
Changes made to the original copy
will not affect any other copy that makes use of the referenced or
stored object. Contrary to the shallow copy, deep copy makes execution of a program slower. This is due to the fact that it makes some copies for each object that is called.