There are 3 different types of messages on Remind.
When you send a class announcement, it is sent to all members of your class. When a participant replies to a class announcement, only the class owner who sent the message will see the response.
You can select up to 9 other participants (totaling 10 in the conversation) to start a group conversation. When you send a message in your group conversation, all participants will see one another as well as the responses. This type of message is popular for group or class assignments.
An individual message is a chat between you and one other participant, only you and the participant can see this type of message.