Simplify the following text for a Grade 4 native English-speaking person.
Original: The term is derived from bookcrossing.com , a free online book club which began in order to encourage the practice , aiming to `` make the whole world a library . ''
Simplified: The term comes from bookcrossing.com , a free online book club which began in order to further the practice , with the goal to `` make the whole world a library . ''