What does the message read receipt mean?

The short message receipt in the mobile phone indicates that the other party has successfully received the short message.

The short message receipt service is a short message value-added service launched by operators for individual users. After using the mobile phone to send SMS normally, the mobile phone will immediately display the words "Message sent". But this only shows that the short message has reached the short message center normally; Doesn't mean the other party received it. The short message receipt service refers to the service that the system sends a receipt to the user in time after the user sends the short message, prompting whether the short message was sent successfully (sending port 10658007). Specifically, it refers to the service that the system sends a receipt to the user in time after the user sends the short message, prompting whether the short message has been successfully delivered.