Dumb kid: An elephant.
Smart kid: A whale.
Me: Yo mamma.
See also Yo Mama.
Nevermind, I was going to tell a joke about time travel, but you didn't like it.
You can take a trip into your internet past on YouTube, as long as you have a Google account associated with all those old videos. Click on your profile picture on YT and then “Your data in YouTube.” See also Internet.