Union Bank of India is a type of public sector bank of India.
It was formed in the year 1919.
It’s headquarter is located in Mumbai, Maharashtra, India.
The bank had 4196 branches in India as on 31 March 2016 and to add to it 4 overseas branches.
As you have asked about the business of the union Bank of India, I am giving you information about it, check below for the details

At the end of March 2015 the Bank achieved total business level of Rs. 5,79,627 crore (Rupees five lakh seventy Nine thousand six hundred and twenty seven crore).

Union Bank has been playing a very proactive role in the economic growth of India.
It extends credit for the requirements of different sectors of economy.
Industries, exports, trading, agriculture, infrastructure and the individual segments are sectors in which the bank has deployed credit to spur economic growth and to earn from a well diversified portfolio of assets.
The Bank has a large clientele base of over 5.7 crores.

It offers following products:
Consumer banking,
Corporate banking,
Finance and insurance,
Investment banking,
Mortgage loans,
Private banking,
Private equity,
Savings,
Securities,
Asset management,
Wealth management,
Credit cards