Summary  
This chapter explains the Linux file permission model by defining three user roles—owner, group, and others—and how to assign read, write, and execute access rights to control file and folder security.  

General domain of usage  
System administration

In **Windows or MacOS**, when you create a file or folder, you can set permissions only for **yourself** or for **all users** on your computer. In **Linux**, there's a bit more control. When you create a file or folder, you can set permissions for three groups of people:

- **Owner**: that's **you**, the one who created the file or folder. You can decide what can and cannot be done with this file or folder, like who can read, write, or delete it;

- **Group**: you can also create a special **group of people** who have access to this file or folder. These could be your **friends or colleagues**. You can set permissions for this group separately from the ones you set for yourself;

- **Others**: these are **all the other people** who use this computer but aren't the owners or part of the group. You can also set permissions for them, determining what they can or cannot do with your file or folder.

This allows you to **control who has access** to your file or folder and **what actions** they can perform. It's an important **security aspect** in Linux that helps protect your data from unwanted changes.


Up to this point, you’ve been performing all actions as **root user**.  The **root user** in Linux has the **highest access rights** and **full control** over the system. They can perform any **system-level operations**.  You’ll learn how to create and manage **new users**, **user groups**, and their **access rights**.

Study More

Who is considered the owner of a file or folder in Linux?

What are the three groups of people you can set permissions for when creating a file or folder in Linux?

Linuxの学習は多くのIT職種にとって価値があります。システム管理者、DevOpsエンジニア、バックエンド開発者にとっては、効率的なサーバ管理、ソフトウェア開発およびデプロイの自動化、サーバサイドアプリケーションの開発と管理を可能にします。ネットワーク管理者、サイバーセキュリティ専門家、データアナリストにとっては、Linuxの知識がネットワークの効果的な管理、セキュリティの確保、データ分析に役立ちます。

Linuxとは何かを学び、その主な利点を探り、なぜ開発者の間で好まれているのかを理解します。コースを通して使用するLinuxディストリビューションを選択します。

仮想環境を構築し、Linuxをコンピュータにインストールすることで、メインシステムに影響を与えることなくコマンドの練習を安全に行うことができます。

ターミナルの使用、ファイルのナビゲーション、プログラムのインストール、システムの更新維持など、基本的なLinuxスキルを習得します。

Linux環境内でユーザーとグループを管理し、ファイル権限を設定し、アクセス権を制御する方法について学びます。

Understanding User Roles Concepts

1. Who is considered the owner of a file or folder in Linux?

2. What are the three groups of people you can set permissions for when creating a file or folder in Linux?