leaving eli5 territory, you imply that they are different, when really, special relativity is a special case of general relativity, the general case. special relativity is general relativity, but while ignoring gravity.
When I was answering, I was keeping it overly simplistic lol. Having kids, I learned a longtime ago to treat topics as 2 separate subjects for an ELI5 explanation.
I instinctively have to answer this question like an ELI5.
With Special Relativity, its speed. For example, suppose you have a magical spaceship that can travel almost as fast as light. You take a trip for what feels like 5 years. When you return to Earth, your friends might have aged 20 years. You’d still be young, but they’d be much older. Time passed differently for you because you were moving so fast.
With General Relativity, its gravity. Einstein said space and time behave a bit like a trampoline. Big things like Earth, the Sun, and planets bend space and time around them. Objects move along those bends, which is why planets orbit the Sun.
Well, guess that’s another subscription down. They’re making this easy for subscribers.