SMS

In short: SMS (short message service) is the short message service of mobile networks, introduced in 1992.

In more detail: An SMS has at most 160 characters (GSM character set). Longer texts are split.

In Depth

Properties

Runs over the signalling of the mobile network, needs no internet connection and is not end-to-end encrypted.

Use and risks

One-time codes (TAN, 2FA), notifications, advertising. Dangers: smishing, SIM swapping and spoofing. Better than SMS codes are authenticator apps (MFA). Successors: RCS and messengers.

See also: Smishing, MFA, 2FA