M1: A measure of money supply that includes all coins and notes in circulation, and personal current accounts. M3: A measure of money supply, including those covered by M2 -- a measure of money, supply, including M1, plus personal deposit accounts -- plus government deposits and deposits in currencies other than rupee.
Repo: repurchase agreements or ready forward deals, a secured short-term -- usually 15-day -- loan by one bank to another against government securities. Legally, the borrower sells the securities to the lending bank for cash, with the stipulation that at the end of the borrowing term it will buy back the securities at a slightly higher price, the difference in price representing the interest.