Post Office Time Deposit Account (TD), This type of accounts arrived in market with Government of India, notification, The National Savings Time Deposit Rules, 1981, and formally established the Time Deposit Account scheme. 
Salient features: 

Duration: 15 year Public Provident Fund Account (PPF )
Interest Rate: 7.1 % per annum (compounded yearly).
Deposit: Minimum INR. 500/- Maximum INR. 1,50,000/- in a financial year.
Frequency of deposit: Deposits can be made in lump-sum or in ​instalments.

5-Year Post Office Recurring Deposit Account (RD)
Interest rates: 6.7​ % per annum (quarterly compounded)
Minimum amount: 100/- per month
Maximum Amount: any amount in multiple of 10/-. No maximum limit.
Account Type: Individual, Joint Account, Guardian on behalf of Minor, Minor above 10 years

Sukanya Samriddhi Accounts can be opened in post office, this type of special account is covered under Government of India, Sukanya Samriddhi Yojna, that entitles special interest rate and features.
Interest Rate: 8.2% annual compounding
Minimum Deposit: 250/- per financial year

Kisan Vikas Patra (KVP) is one of the available saving certificate scheme in India that one can subscribe from Post Office. It is more like fixed deposit scheme of any bank, however differs significantly due to its distinguished feature and authority of scheme.

Post offices in India offering banking services since 1882, after establishment of The Post Office Savings Bank of India (POSB) in 1882.

earlier post office savings bank account passbook entry where manual with typical post office date stamping method what we used to see in postal stamp above our postal delivery envelops.