A wireless router helps all the devices in your home connect to the internet. While most modems can only handle one device at a time, users with multiple devices generally connect their modem to a router. All your devices then connect with the router and get proper internet access. Furthermore, some ISPs also provide a wireless modem - but the problem is that they have a very limited range. Hence, connecting the modem with a router helps ensure that you get internet access all over your home across all the floors.