An SSID is the name assigned to a wireless network. "SSID" stands for "service set identifier." SSIDs are case-sensitive text strings of alphanumeric characters (letters or numbers) and have a maximum length of 32 characters.
A wireless router typically has an SSID set by default. The name can be manually changed on the router's configuration page. SSIDs are broadcast publicly by default, but the user can choose to hide it for added security. If the user hides the SSID, he or she must manually enter the identifier into the device when connecting to the network. If there are multiple wireless routers on the same network, the user may want to set all SSIDs to the same name.