The sender ID is the phone number or unique name that appears in the "from" field of a text message. You can choose to use your business's phone number as the sender ID or all or part of your business name (you have up to 11 characters, so you may be limited if your business name is longer).
You need to register the sender ID before you can start using it with your messages. Red Oxygen makes it easy to register your ID.
Sender ID is only available in select countries and is currently not usable in the United States and Canada.