What Does Service Set Identifier (SSID) Mean?
A service set identifier (SSID) is a type of identifier that uniquely identifies a wireless local area network (WLAN). Service set identifiers differentiate wireless LANs by assigning each a unique, 32-bit alphanumeric character identifier.
An SSID is also known as a network name.
Techopedia Explains Service Set Identifier (SSID)
A service set identifier is primarily designed to distinguish a wireless local area network in locations where other WLAN might also be broadcasting simultaneously. A service set identifier works in collaboration with a basic service set (BSS), a combination of access points and connected clients, and an extended service set (ESS).
SSID is used to group and identify the ESS so that a new host connecting to this network can easily identify and connect to it. For example, all access points and host stations must specify the correct SSID of their ESS in order to authenticate and gain network connectivity.