The call money market deals in short-term loans between banks with maturities ranging from 1 day to 2 weeks. It provides banks a source of highly liquid funds to meet temporary shortfalls or surplus. Key participants include commercial banks. Call rates fluctuate daily and even hourly based on demand and supply in the market. Rates also vary across cities due to differences in liquidity. Volatility is driven by factors like banks borrowing to meet reserve requirements, occasional disruptions, and interventions in foreign exchange markets that impact liquidity.