Form 16 is your salary TDS certificate. If your income from salary for the financial year is more than the minimum exemption limit of Rs 2,50,000 your employer is required by the Income Tax Act to deduct TDS on your salary and deposit it with the government.
Form 16A is also a TDS Certificate, applicable for income other than salary income
All details that are there in Form 16A are available on Form 26AS.
suppose you have declared some amount as total income but omitted to include some interest income which has been included in Form26As, the IT department can ask for clarifications and if not satisfied can make adjustments and ask you to pay tax within a particular period of time.
Basically with computerisation having taken place, all incomes get recorded-be it TDS on FD or not mentioning SB interest.
Share transactions are cross checked by IT with NSDL database using PAN,
It becomes incumbent on every tax payer to be very careful to declare all his income from various sources.
11th January 2018 From India, Pune