Form 16 is essentially a certificate issued by the employer, stating that TDS has been deducted and deposited with the government on behalf of the employee. It has two components, Part A and Part B.
FORM 16 PART A - The employer can download this part of the form through the TRACES portal. - This has to be issued to every employee, stating the amount of TDS deducted and deposited with the government. - It also contains other details like the PAN, TAN of the employer, PAN of the employee, Assessment Year etc. - If a person has changed job within a financial year, then both employers will have to issue separate Part A of Form 16.
FORM 16 PART B - It is in the form of an annexure to Part A, containing detailed salary breakup, detailed breakup of exempted allowances, deductions allowed under the Income Tax Act etc. - If a person has changed job within a financial year, then the employee may decide as to whether he wants this part from both the employers or the last employer.