There are three types of telephones: corded telephones, cordless telephones and internet telephones. a corded phone needs to be connected to a phone line and is suitable for home and office use. the cordless phone can be moved freely, suitable for large offices and families. the internet phone can save call charges through the network connection, and is suitable for enterprises and individuals. the three types of telephones have their own advantages and disadvantages, and users can choose according to their needs.