What is Dark energy?

Dark energy is like a hidden push that makes everything in the universe move apart from each other.

Imagine you're blowing up a balloon, as it gets bigger, the dots on its surface get farther away from each other. Now picture the whole universe as that balloon, and dark energy is what keeps blowing it up, making galaxies zoom away from each other.

Think of the universe like a stretchy playground mat. When you step on it, it stretches out, everything on the mat moves apart. Dark energy is like an invisible force that’s constantly stretching this mat, even when no one is stepping on it. It's not magic, just something we can't see but can feel through how things are changing.

What makes dark energy special is that its push gets stronger as the universe grows, like a spring that keeps getting tighter the more you pull it. This means the universe isn’t just expanding, it’s accelerating, and dark energy is the reason why.