In C#, there are several ways to pass parameters to a method:

By value (default): Passes a copy of the parameter’s value to the method. Changes to the parameter value inside the method do not affect the original value.

By reference using ref: Allows the method to modify the value of the parameter directly. The parameter must be initialized before passing it to the method.

By reference using out: Similar to ref, but the parameter does not need to be initialized before passing it to the method. It’s typically used when the method returns multiple values.

By reference using in (C# 7.2 and later): Passes the parameter by reference, but it’s treated as read-only within the method. This is useful for large value types to avoid unnecessary copying.

Using params keyword: Allows methods to accept a variable number of parameters of the same type. Parameters passed using params must be the last in the parameter list.

Using named parameters: Allows calling methods by specifying the parameter name along with the value. This can improve code readability, especially when dealing with methods with many parameters.