Before April 1, 2009, if you had to use the ATM of any bank with whom you don't have any banking relationship, you ended up paying fees. It meant you had to find the closest ATM belonging to your bank to withdraw cash and make balance inquiries. So RBI introduced a directive to the banks to allow free use of ATM machines irrespective of which bank a customer had accounts with.
This meant that irrespective of which bank you bank with, you could use any other bank's ATM free of cost.
However, now The Reserve Bank of India has decided to put a cap of Rs 10,000 per withdrawal in such (third party) transactions. Also, the number of such transactions will be limited to five times a month from 1st october 2009.
The Indian Banks Association (IBA), proposes to levy a transaction fee of Rs.20 per transaction for using another bank's ATM, Beyond five transactions.