Superuser

The whole machine — boot to containers.

For systems & platform engineers. The complete arc: boot, systemd, namespaces, cgroups, and the punchline — a container is just a process wearing a costume.

Lessons in this path

• The Round Trip — Watch one command travel and return.
• The Filesystem Tree — Everything is a file. Walk the tree.
• Reading & Writing — See where text goes when you read and write.
• Permissions — the gate — Watch the kernel check if you're allowed.
• Names vs Things — inodes & links — A filename is a label, not the file.
• From Program to Process — Watch a program on disk come alive in memory.
• The Process Tree — Every process has a parent. Meet PID 1.
• fork() & exec() — See one program become two, then something else.
• Process States — A process is a state machine.
• Signals — Processes talk by sending signals.
• Pipes & Redirection — Wire one program's output into another's input.
• The User/Kernel Boundary — Cross the wall between your code and the kernel.
• Inside the Kernel — Meet the kernel's organs.
• Virtual Memory — Every process thinks it owns all the RAM.
• The Process Address Space — See where code, data, heap, and stack live.
• Scheduling & Context Switch — One CPU, many processes, taking turns.
• Boot — the ignition chain — Watch the machine wake up.
• systemd — How services start in the right order.
• Namespaces — Wrap a process so it sees its own world.
• cgroups — Put a process on a resource budget.
• "A Container Is Just a Process" — Assemble the thing you already use every day.