Final answer:
A copy constructor is a special constructor in object-oriented programming that initializes an object using another object of the same class. Its one parameter is a reference to the object from which to copy the data.
Step-by-step explanation:
A copy constructor in object-oriented programming languages like C++ is a special constructor that initializes an object using another object of the same class. The one parameter that a copy constructor takes is a reference to an object of the same class, which is used as the source of the data for the initialization. The syntax for a copy constructor typically looks like this:
ClassName(const ClassName& other);
Where ClassName is the name of the class, and other is the name of the parameter, which is a reference to an instance of ClassName. What makes the copy constructor unique is that it enables the creation of a new object as a copy of an existing object. For example, if we have a class Student, a copy constructor might look like this:
Student(const Student& other);
The purpose of such a constructor is to ensure that when a new object is created as a copy, it is done efficiently and correctly, especially when the class involves dynamic memory allocation or other resources that need to be managed.