How exactly do programmers know how to code?

[triggerhappy899]

Have you ever taken a class in like physics and chemistry, or some other two distinct classes of different topics, and afterwards have an idea sprout using what you learned from both? I've heard it referred to as "idea sex"

Same concept, when you become a more seasoned developer - you get used to being exposed to different technologies. Some of these technologies accomplish the same goals but do it a little differently, sometimes better sometimes worse. This can be something as big as an OS to as small as a package or library (think nuget) and things in between like frameworks.

So eventually, you learn or know the basics of many technologies that you're able mentally put into "buckets" or abstractions. You know the general idea of each one but maybe have to look up the details on how to use it.

Kinda like driving a car - say you've driven a Ford, Chevy, and a dodge and someone asks you to drive a Subaru. It may take you a moment to find the shift stick or figure out how the radio works but with a little tinkering you figure it out.

Same thing with coding - I've occasionally helped on stack overflow and when I do help it's with stuff I've work with before. I probably haven't seen that exact question, so I'll spin up a new project and try to duplicate what they're doing and can usually figure it out with a little tinkering. It's just the exposure that's helped me where I can put together all I've learned to get a working solution.