Cpp and h files in one folder?

I don't know if it's okay to ask questions like this, but I'm asking because I'm curious about which one is mainly used.

In a large project, for example, if you create a class A, you create an A.cpp, A.h file, and you put these two files in one folder to manage them Create folder A in the source folder, and create folder A in the header folder to manage it.

It's a really useless question, but there's no place to ask, so I'm posting a question. Is this also a method of separation according to individual tendencies?

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