What is a Sender ID?

Sender ID :- 

Sender ID is a set of characters that represent the identity of a sender. For example, when you receive a regular SMS from a friend, her/his name (as stored in your contacts) is displayed as a Sender. Similarly, when a business sends an SMS to its customers, a numeric or alphabetic set of characters represents the company or brand name.

Sender ID for Promotional SMS is numeric and is decided by the operator. For example 777777

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Sender ID for Transactional SMS is 6 alphabetic/alphanumeric characters in India. For example: NOTIFY, MSGIND, MSGG91. For other countries, the sender ID format may vary according to the rules of a particular country.