BTW did you know that ancient people knew about computers, the steam engine and batteries?
I'm not quite sure which computer you're thinking of, but I just wanted to chime in to say "no" to these two inventions. No, ancient people did not know about the steam engine and no, they did not know about batteries. Those are two common misconceptions.
They had objects that worked with the same basic principles modern steam engines and batteries use, sure, but both lacked the key thing to make them similar to the actual stuff: produce useful amounts of work and energy, respectively. And that's where later inventors had to put their work into.
You can't use Hero's "steam engine" to power anything, it's far too weak for that. As soon as you put anything on it to move beside itself, it will most probably stop moving.
Even in modern times, countless people before James Watt built steam engines, but they all had horrible efficiency and thus weren't used very often.
They can be called steam engines, however, because they
actually did some work that went further than moving itself.
As for the Baghdad battery, it's very much unknown if this wasn't just an accidental battery that "worked" because someone put two different metals and an electrolyte (read: a mug, a spoon, and lemon juice) together. Even if it wasn't an accident, however, the same thing mentioned above applies. The amount of electric energy such a "battery" would produce couldn't be used for anything.
Even in modern times, it took (literal) ages for people to understand the connection between static electricity known for millennia and the thing batteries created. And even after that, someone first needed to connect a couple
hundred batteries in parallel and series (to get both enough voltage as well as current) to demonstrate it's actually useful for something (in that case, generating light).
