PAN also referred as Permanent account number is a 10 Digit Alphanumeric code that identifies individual tax payer allotted by income tax department of india. It is supervised by central board of direct taxes. In india PAN card can also be used as a identity proof.
Using PAN number of a indian citizen the government can track his/her financial transactions universally across all of their bank accounts. This paves a way to easily track the person's deposits and expenses he made using any of his/her bank account.
Using PAN you can apply for many other government services like aadhar card, bank account , debit card, credit card and more.
PAN number cannot be changed for one person ,getting multiple pan card for one person is illegal. You must surrender the other pan card at your local income tax office.