Laptops have built in batteries. Once the battery in your laptop is charged, you will be able to use it without connecting it to a power source. Laptops can also connect to the Internet without a cable, with the help of wireless routers and wireless cards. This wireless connection allows the laptop to pick up Internet signals similar to how a radio picks up radio waves. Wireless routers are devices that offer a wireless signal. A router sends a signal into the air that the wireless-ready devices pick up and this allows a user to surf the Internet. Wireless cards are of two types: built-in and add-on. Built in wireless cards make the laptop capable of connecting to a wireless router by finding the connection over the airwaves. Ad-on wireless cards are cards that need to be attached to the laptop to provide the same function.