When you make a phone call, you talk to the person on the other end. The time you spend talking to them is called call duration. When you make many phone calls, you can add up the call durations and divide by the number of calls to get the average call duration. This is like counting how much candy you have and sharing it with your friends so everyone gets an equal amount. The average call duration helps people understand how long their conversations usually last when they make phone calls, just like you can understand how much candy you have to share with your friends.