Round-trip time

Round-trip time is the amount of time it takes for a message to go from one place to another and then come back again. Imagine you are playing catch with your friend. When you throw the ball to your friend, it takes some time for it to get to them. They then catch the ball and throw it back to you, which also takes some time. The amount of time it takes for the ball to go from you to your friend and then back to you again is the round-trip time. In the same way, when you send a message online, like an email or a text message, it takes some time for the message to get to the other person's device and then for their device to send a response back to you. The total amount of time it takes for your message to go to the other person and then for their response to come back to you is the round-trip time.