What is the difference between typeof(), GetType() and is?

typeof() takes a type name specified at compile Time.

GetType() gets the Type of an Object at runtime

is returns true if an instance is in the inheritance tree. Since the is Keyword is casting the object, you should use it with care.

here is an example.

class Employee { } 
class Developer : Employee { }

void PrintTypes(Employee e) { 
    print(e.GetType() == typeof(Employee)) // false 
    print(e is Employee)                   // true 
    print(e.GetType() == typeof(Developer))    // true
}