| ### 🛡️ **Secure by Design** Linux is built with security in mind | ### 🏠 **User Isolation** Users can only modify files in their home | ### 👑 **Administrator Control** System changes require root | ### 📖 **Read-Only System** System files are read-only for users |
| 📖 Read (r) | ✏️ Write (w) | ▶️ Execute (x) |
|---|---|---|
| **For Files:** - View file contents - Copy the file **For Directories:** - List directory contents - See files inside | **For Files:** - Modify file contents - Delete the file - Rename the file **For Directories:** - Create files inside - Delete files inside - Rename files inside | **For Files:** - Run file as program - Execute as script **For Directories:** - Enter the directory - Access files inside |
# File permissions visualization
-rw-r--r-- 1 alice users 1024 Feb 8 10:30 report.txt
│││ │ │ │
│││ │ │ └─ Others: read only
│││ │ └─── Group: read only
│││ └───── Owner: read + write
││└─────── Owner (alice)
│└──────── File type (- = regular file)
└───────── Permissions
drwxr-xr-x 2 bob users 4096 Feb 8 11:00 documents/
│││ │ │ │
│││ │ │ └─ Others: read + execute (can list)
│││ │ └─── Group: read + execute (can list)
│││ └───── Owner: full access
││└─────── Owner (bob)
│└──────── Directory (d)
└───────── Permissions
| Permission | Files | Directories |
|————|——-|————-|
| r (read) | 📄 View content | 📋 List contents |
| w (write) | ✏️ Modify content | 🗂️ Create/delete files |
| x (execute) | ▶️ Run as program | 🚪 Enter directory |
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