ELI5: Explain Like I'm 5

Midnight

Midnight is when the clock strikes 12:00 at night. This is the time when it's very dark outside and most people are sleeping in their beds. It's like the middle of the night, but it's also the start of a new day. When we go to bed and wake up the next morning, we call that "one day." So, when we cross over from 11:59 PM to 12:00 AM, we are starting a new day. It's like saying, "Goodbye today, hello tomorrow." This happens every day, so we always have a chance to start fresh and new each day at midnight.