# Using the operator Keyword

In C#, operators are static methods. The return value of an operator represents the result of an operation. The operator’s parameters are the operands.

You can define an addition operator for a `Fraction`

class as you would any other class method, but with a bit of a difference. Instead of a method name, you use the C# syntax of combining the `operator`

keyword with the plus sign (`+`

) operator, combined with the keyword `static`

. For example, the overloaded addition operator (the `operator+`

method) takes two `Fraction`

objects (the fractions you want to add) as parameters and returns a reference to another `Fraction`

object representing the sum of the two parameters. Here is its signature:

public static Fraction operator+(Fraction lhs, Fraction rhs)

And here’s what you can do with it. Assume, for instance, that you’ve defined two fractions representing the portion of a pie you’ve eaten for breakfast and lunch, respectively. (You love pie.)

Fraction pieIAteForBreakfast = new Fraction(1,2); // 1/2 of a pie Fraction pieIAteForLunch = new Fraction(1,3); // 1/3 of a pie

The overloaded `operator+`

allows you to figure out how much pie you’ve eaten in total. (And there’s still 1/6 of the pie leftover for dinner!) You would write:

Fraction totalPigOut = pieIAteForBreakfast + pieIAteForLunch;

The compiler takes the first operand (`pieIAteForBreakfast`

) and passes it to `operator+`

as the parameter `lhs`

; it passes the second operand (`pieIAteForLunch`

) as `rhs`

. These two `Fraction`

s are then ...

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