Lvalue
* Refers to a memory location
* Represents a variable identifier
* Mutable
* May appear on the left or right side of the = operator
For example : In the statement x =20, x is an lvalue and 20 is an rvalue.
Rvalue
* Represents a data value stored in memory
* Represents a constant value
* Always appears on the = operator’s right side.
For example : The statement 10 = 20 is invalid because there is an rvalue (10) left of the = operator.
