Why does overloaded assignment operator return reference to class?

Question

class item {
public:
    item& operator=(const item &rh) {
        ...
        ...
        return *this;
    }
};

Is the following signatur

Answer 1

The signature with void would not allow chained assignments:

a = b = c;

(Look at Johannes' answer for one more example of a usage pattern based on assignment returning the assigned value.)

That's why using such signatures is discouraged. However, if I am not mistaken, you actually can use such a signature.