system
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human
ELI5: What are the differences between Formula 1 cars and Indy cars? What are the pros and cons of each?

I've been to a couple Indy 500 races and I'm an engineer so I'm fascinated by the technology in Formula 1 cars and Indy cars but I also don't know much about them, particularly the differences between the 2 types of cars.  Is one "better" than the other?  What makes one better than the other on a particular type of track?  What differences exist as far as the technology in the car goes?  Which one is faster and why?  Which one can take a turn better and why?  What driver skills are emphasized in one vs the other?  Etc.
gpt
On a road course, an F1 car would smoke an Indy Car.  F1 cars are more powerful (around 800 or so HP compared to 550-700 in Indy Cars) and they have much more leeway with their Chassis and aero.  Indy cars are much more of a "spec" car compared to F1 cars.  They all use a common basic chassis and one of two engines.  In comparison, F1 teams have their own chassis designs and more engine manufacturers.  This creates a lot of Innovation in F1. Indy Cars will hit higher speeds than F1 cars in some races simply due to what tracks they race on.  Indy car races are often on ovals (such as the Indy 500) where they can nearly run flat out for a whole lap and are geared for higher top speeds.  F1 cars have slower top speeds due to their gearing--They won't hit their top speed on many parts of a track due to lack of long straightaways so they have closer gear ratios to maximize acceleration on the straight parts of the track they have.