Nota bene is a fancy Latin phrase that simply means "note well" or "pay attention". It's often used as a reminder to tell someone that something is really important, so they should make sure they remember it. It's like when your mom tells you to remember to take your lunchbox to school in the morning, and she says "nota bene" to make sure you don't forget. So, if someone says "nota bene" to you, just listen up and be sure to pay close attention to what they're saying!