what object representation in builder pattern exactly means?

I'm a newbie for design pattern.I feel I missing some essential pieces in understanding Builder Pattern. what the object representation exactly means in this definition?

THE BUILDER PATTERN: Separates the construction of a complex object from its representation so that the same construction process can create different representations.

Is it means the object's internal struct(instance variable and member function)? I has look for on Internet but still confuse it,any help is appreciated!