Time Deposits are risk-free investments by the India Post that comes with fixed maturity periods. As the name suggests, the deposit and the return on these investments are ‘time-based’. This makes them risk-free. Additionally, time deposits are not for regular investing but one-time lump sum (bigger than normal regular savings) investments.
In a TD, you can choose an amount and the duration for which you want to invest. For that period, the amount is locked in (meaning, you cannot withdraw it without incurring penalties). You get the interest on your Time Deposit in your savings bank account. Your investment will be returned to you when the maturity period is over.

Example:
Fixed deposits and Recurring deposits are and example of time deposit accounts