Free SMS does not require registration.

There is software that can send messages to the other party for free, without the other party installing the client. For example, users of Yixin and Fetion can send short messages for free. You can send text messages for free as long as you agree to be friends.

Short Message Service (SMS for short) refers to the text or digital information directly sent or received by users through mobile phones or other telecommunication terminals. The number of characters that users can send and receive SMS at a time is 160 English or numeric characters or 70 Chinese characters.

A client or client refers to a program corresponding to a server that provides local services to customers. Except for some applications that only run locally, they are generally installed on ordinary clients and need to work with the server.