The Service Set Identifier (SSID) is the name of a wireless network. It’s what you type into your phone or laptop when you want to connect to the internet wirelessly. It’s also often called an access point name because it identifies the specific access point that someone wants to use. The SSID is how Wi-Fi networks are uniquely identified and differentiated on a given frequency band to prevent signal interference between them.
The SSID can be up to 32 characters long and should not include any spaces or special characters, nor should it start with “0x,” which indicates hexadecimal notation for IPv4 addresses. For example, if your wireless router has been set up with the SSID “Joe’s Office,” others can connect to it by entering that name in their computers’ or phones’ Wi-Fi menus.
You’ll want to change your network’s SSID so you can easily distinguish it from other wireless networks in your area or even from nearby rooms within the same building. Otherwise, if you live in a condo complex, for example, and several wireless networks are operating around you, any computer on one of those networks will be able to see the names of all the other networks in range (which would include yours as well). Instead of just connecting to yours, they might get confused about which one to use and wind up trying them all—at which point they could wind up tapping into your neighbor’s network, not yours. Changing the name of your wireless router to one that differentiates it from other nearby routers can prevent that sort of confusion and protect the privacy of your data.