Rich Communication Services protocol is like an updated version of text messaging, which combines the old manner of texting and modern messaging together. It takes features from platforms like Facebook, iMessage, Messenger, and WhatsApp, and makes your SMS look like an iMessage message. The RCS also allows you to send high-resolution images, audios, videos, and create group chats in order to make the communication between you and your customers more fun.
Sometimes RCS is confused with Verified SMS (link here to the Verified SMS article), as it is also a way to send branded mass texts. However, Verified SMS is mostly used to make your text messages more credible and secure and does not offer all of the other features that RCS has.