What do the codes in your SMS mean?

Have you ever received an SMS from your bank, service provider, or a company, that has been prefixed with codes? For example: An SMS from ICICI Bank that reads: IZ-ICICIBANK. Ever wondered what these codes really mean?

Telecom Regulatory Authority of India (TRAI) introduced these codes in order to curb bulk SMS providers from unsolicited commercial communication. Now that these codes are implemented, the sender can be traced, if necessary, as these codes reveal the location, the name of the company and the service provider.
This is how the code should look like:
XY-name of the company

X = Code of the service provider

Y = Location

Which means, IZ-ICICIBANK would be:

I = Idea Cellular (service provider)

Z = Maharashtra (location)

A list of Service Provider codes & Service Area codes: