🖥️ Basic Linux Commands

📂 1. Listing Commands (ls)

• ls → 📋 List files and directories.

• ls -l → 📜 Detailed list with permissions, size, owner, etc.

• ls -a → 👀 Show hidden files.

• ls -lh → 📏 Human-readable file sizes.

• ls -d */ → 📁 List only directories.

• ls *.sh → 🛠️ Show only .sh files.

🔹 Example:

ls -lh
ls -a

📁 2. Directory Commands

• pwd → 📌 Show current directory path.

• cd folder → 🔄 Change directory.

• cd .. → ⬆️ Move one level up.

• cd - → 🔙 Switch to previous directory.

• cd ~ → 🏠 Go to the home directory.

📂 Creating Directories (mkdir)

• mkdir newFolder → 🏗️ Create a new folder.

• mkdir .NewFolder → 👀 Create a hidden folder.

• mkdir A B C D → 📂 Create multiple folders at once.

• mkdir /home/user/Mydirectory → 📍 Create a folder in a specific location.

• mkdir -p A/B/C/D → 🔀 Create nested directories.

🔹 Example:

mkdir newFolder
mkdir .NewFolder
mkdir A B C D
mkdir /home/user/Mydirectory
mkdir -p A/B/C/D

📂 Deleting Directories (rmdir, rm -r)

• rmdir folder → ❌ Remove empty directory.

• rm -r folder → 🚨 Remove non-empty directory.

🔹 Example:

rmdir emptyFolder
rm -r oldFolder

📄 3. File Management

• touch file.txt → 📄 Create a new empty file.

• cat file.txt → 📖 View file content.

• cp file1 file2 → 📑 Copy file.

• mv old new → ✏️ Rename/move file.

• rm file.txt → ❌ Delete a file.

• vim file.txt → ✍️ Open file in the Vim text editor.

🔹 Example:

touch notes.txt
cp notes.txt backup.txt
rm unwanted.txt
vim myfile.txt

🔎 4. Searching Files & Text

• find /path -name filename → 🔍 Find file by name.

• grep "word" file.txt → 🔎 Search inside a file.

🔹 Example:

find /home -name "notes.txt"
grep "error" log.txt

⚙️ 5. System & Process Management

• df -h → 💾 Check disk space.

• free -m → 🔋 Check RAM usage.

• top → 📊 View real-time system processes.

• kill PID → ❌ Stop a process of mentioned process ID (PID).

🔹 Example:

df -h
top
kill 1234