system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Entropy, please oh god please.

I have read COUNTLESS explanations, countless examples, countless ELI5s. But I still have no fucking idea what entropy is. I’m **not** leaving this earth before I understand what it is. Thank you.
gpt
Over time, shit changes to the temperature of the things next to them. This is true for literally everything, so the temperature of the earth is slowly equalizing to the temperature of the space next to it ( which is very technically not a vacuum since there's tiny particles in it).

"Entropy" is that idea. Things slowly lose their energy over time until the system has equal energy in it, and then nothing can change since it's perfectly equal.

"Heat Death", often referred to along with entropy (so i'm guessing you want an explanation for that too) is when literally everything over trillions of years perfectly equalizes it's heat, and then perfectly equalizes all of it's other forms of energy in the form of heat because heat is bled off every time there's an action (usually in the form of friction). Eventually, literally everything will be an evenly distributed evenly "room temperature" blob, and because there's literally no potential energy left literally nothing more can happen.

*edit: entropy is also a word which can be used when not referring to the physics concept, and in that case it simply means the general concept of stuff eventually falling apart and becoming useless.