Can a process running in one container see process of another container?

Hi,
I have some mixed information about container security. In some websites, it has been mentioned that “Process running in one container can see a process running in other container” and in Docker document website it is mentioned as “…cannot see”.
It is misleading.

Please clarify.

Thanks in adv,
Vish

Could you link to the articles which claim that processes are visible between containers? I can’t think of a case where that would be true, but maybe the other articles give some examples.