Question:
What is the SMS Sender ID for?
Answer:
Sender ID is for SMS sender branding.
Example: Your Sender ID is MyBrand. When you send a text message, your subscriber will receive a text with MyBrand as the sender instead of receiving a random number.
Please note that Sender IDs need to be approved first. Once approved, only then will you be able to use it on your SMS automation. You can check your Sender ID dashboard to see the approval status of your Sender ID.
Sender IDs are free of charge and you can have as many as your brand needs, though it's really rare that a single brand will need to have many sender ID.