Connect your modem to your phone with USB to modem cables, or DB9 to DB25 cables. Modem cables are still necessary as these little signal messengers can connect you to the cyber world. The World Wide Web can hardly be accessed in your home without a modem or a WiFi hub or adapter. As it is, modem cables are like roads that converge reality and the World Wide Web. They are one of the necessary components that link us to the rest of the world, actually.