Main monetary instruments of the ECB

There are two kinds of instruments for the ECB.
1) Open market operations: These instruments are important for controlling the interest rates as well as liquidity. The most important open market operation is the main refinancing operation. The main refinancing operations have a duration and frequency of one week.

2) Standing facilities: Standing liquidities are used to handle short term (overnight) liquidities. These instruments are not initiated by the Central Banks but rather by the counterparties (commercial banks) The marginal lending facility is used by commercial banks to borrow overnight liquidity from the Central Banks. The deposit facility is used by commercial banks to make overnight deposits at the central bank