What is the difference between Volume, Buy Quantity and Sell Quantity?

While going through end of day statistics for a particular FNO Scrip, I found buy and sell quantities to be different which is contrary to my understanding that for every buy, there is a sell. And volume figures were totally different. So if anyone can explain the difference in volume, buy quantity and sell quantity?

Hello Trader,

EOD Volume = QTY actually bought and sold during the day.

EOD BUY QTY = QTY offered for purchase by buyers but has not matched with a seller at the end of day

EOD SELL QTY = QTY offered for sale by sellers but has not matched with a buyer at the end of day.