Smart Message vs Auto Reply

What is the difference between a Smart Message and an Auto Reply? 

Smart message requires an outgoing message to sent and prompt recipients for a yes/no, multiple choice or numeric based response. Based on their response, Mongoose will automatically send a pre-configured follow up message based on the predetermined 24, 48 or 72 hour response window.

Auto Reply does not require an initial outgoing message and utilizes the matching of customizable keywords. There is no reply time window like smart messages. A contact can text into Mongoose a keyword and receive a pre-configured auto reply follow up message.

Note: You can choose to compose an outgoing message to prompt a reply of a keyword, but an outgoing message is not required.