The present invention relates to a home appliance which can communicate with an outside of the home appliance, an online system and a method for using the online system including the same. According to embodiments of the present invention, a method for using an online system may be provided including the steps of log in a server by transmitting user information to the server through an external terminal, selecting a laundry machine of which course updating is desired through the external terminal and transmitting the same to the server, receiving updatable course information from the server, and displaying the information on the external terminal, selecting an updating desired course through the external terminal, and transmitting selected course information to the server, and updating the laundry machine with the selected course through the server.