If you have ever worked with Linux, you have probably heard the term “process”. But what exactly is a Linux process, how does it work and why is it so important for system administration, performance and security?

In this blog, I will dive into Linux processes step by step starting from the basics and moving towards advanced concepts. Whether you are a beginner exploring Linux for the first time or an experienced sysadmin, this post will level up your understanding.

What is a Process in Linux?

A process in Linux is simply a program in execution.

Whenever you run a command or application, Linux creates a process for it.

Example:

$ firefox

When you run this command, Linux creates a new process for Firefox.

Each process is assigned a Process ID (PID) which makes it uniquely identifiable.

Key Components of a Process

• PID (Process ID) → Unique number to identify each process.
• PPID (Parent Process ID) → The process that started (parent) the current process.
• UID (User ID) → The owner of the process.
• Priority & Scheduling → Determines how CPU time is shared.
• State → Running, Sleeping, Stopped, or Zombie.

You can check running processes with:

ps aux