For most operating systems, threads each have their own stack space, and (if supported) thread-local storage, but share heap, constants (.bss), and static varia

For most operating systems, threads each have their own stack space, and (if supported) thread-local storage, but share heap, constants (.bss), and static variables (.data). It's impossible to say exactly what resources a given thread is using from those shared resources, so htop just includes them all, for every thread.