"Hi, Amigo!"

"Hi, Julio."

"It's good to see you. How are you feeling?"

"I feel energized. I've solved nearly every task in this level."

"If you've solved everything, then it's time to watch a video."

Java Collections, level 9, lesson 13
How does caffeine keep us awake?
Grab a cup of coffee, because you’ll desperately need it while watching this video :) You’ve probably heard about the pros and cons of caffeine. It can raise your blood pressure and make you feel anxious. But somehow it can also make you feel more focused, happy and energetic, even if you haven’t gotten enough sleep. Let’s figure out how it works.