There are three types of applications:
1) Application for allotment of PAN (Form 49 A)
This application should be used when the applicant has never applied for a PAN or does not have PAN allotted to him.
2) 'Request for New PAN Card or/and Changes or Correction in PAN data'
This application should be used when PAN has been allotted already to applicant but a new PAN card is required or when data associated with the PAN (e.g. name of applicant / date of birth / address) is required to be updated in the records of Income Tax Department.
3) Application for allotment of PAN (Form 49AA) - applicable for foreign citizens
This form should be used when the applicant has never applied for a PAN or does not have PAN allotted to him. An applicant can visit Income Tax Department (ITD) website to find whether a PAN has been allotted to him or not.