In the interaction tab you can measure the amount of interactions, i.e. messages, quick-replies, buttons, etc. that have been pushed and sent between the bot and the users.
The first two numbers show you the total number (bot + user) of interactions vs the number of user-interactions.
Messages by sender shows how the amount of total messages are divided between the chatbot and the end-users.
Lastly, we have an overview of the user messages by type, where we can e.g. see the amount of text messages vs. quick replies.