This denotes for what type of content in your messages you are obtaining consent. The content can be defined by the source of the message (available with Start) or the Content Type (available with Grow).

Most regulations look at obtaining consent for automated or bulk SMS so you have to be careful while sending Content from different sources. A manually typed message is treated differently than a bulk or an automated SMS. 
There are two options for defining what you obtaining consent for:

Source Type – You can define if the source requires a prior consent or not. For example,  you might not require consent for sending an Emergency message. Another scenario is that you might not be required to use SMS-Magic Compliance Center because you have built your own compliance center. So you can choose, “Consent Not required”.

Content Type – Content type opt-ins are useful in ensuring that you can continue sending messages to customers for a specific content-type. Therefore, in case the customer is applying for a blanket opt-out instruction, in the opt-out confirmation message they receive, you specify the content type opt-in they can send if they wish to continue receiving messages for that specific content type.  

For more information about configuring consent, see Messaging Compliance.