Not every container has an operating system inside, but every one of them needs your Linux kernel.
Before going any further it's important to understand the difference between a kernel, an operating system, and a distribution.
- Linux kernel is the core part of the Linux operating system. It's what originally Linus wrote.
- Linux OS is a combination of the kernel and a user-land (libraries, GNU utilities, config files, etc).
- Linux distribution is a particular version of the Linux operating system like Debian or CentOS.
To be technically accurate, the title of this article should have sounded something like Does container image have a whole Linux distribution inside? But I find this wording a bit boring for a title 🤪