Have been receiving sms codes: DT-BJP, TA-ICICI, AX-Airtel etc?

[kirank]

HI,

Have been recieving AT-Citibank ,VX-Citibank, TA-Spicejet,TM-Yatra,AM-ezeego,AX-Airtel etc.

Any idea what it is and how they derive this?

Regards
Kiran Katti.