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Aisalkyn Aidarova
Aisalkyn Aidarova

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simple Linux commands

βœ… So these are SAME: 

cd ~
cd /Users/jumptotech
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πŸ”Ή Correct usage examples

Go to home: 

cd ~
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Go to Desktop: 

cd ~/Desktop
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πŸ‘‰ Expands to:

cd /Users/jumptotech/Desktop
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Create file in home: 

touch ~/file.txt
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πŸ”Ή Absolute vs Shortcut

Type Example Meaning
Absolute /Users/jumptotech/Desktop Full path
Shortcut ~/Desktop Same, shorter

πŸ‘‰ ~ ONLY works at the beginning

βœ… Correct:

~/Desktop
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❌ Wrong:

/Desktop/~
/Users/jumptotech/~
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πŸ”Ή Real DevOps Example

When installing tools:

mv terraform ~/bin/
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πŸ‘‰ Means:

/Users/jumptotech/bin/
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πŸ‘‰
β€œ~ is a shortcut for your home folder.
Don’t mix it with full paths.”

πŸ”₯ Interview answer (short)

πŸ‘‰
β€œ~ represents the current user’s home directory. It is a shortcut used instead of writing the full absolute path.”

πŸ”Ή 1. Navigation Commands

pwd

πŸ‘‰ Show current directory

pwd
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ls

πŸ‘‰ List files and folders

ls
ls -l     # detailed view
ls -a     # show hidden files
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cd

πŸ‘‰ Change directory

cd /home/ubuntu
cd ..        # go back one folder
cd ~         # go to home
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πŸ”Ή 2. File & Directory Management

mkdir

πŸ‘‰ Create folder

mkdir project
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touch

πŸ‘‰ Create empty file

touch file.txt
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cp

πŸ‘‰ Copy files

cp file.txt backup.txt
cp -r folder1 folder2
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mv

πŸ‘‰ Move or rename

mv file.txt newfile.txt
mv file.txt /home/ubuntu/
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rm

πŸ‘‰ Delete files/folders

rm file.txt
rm -r folder
rm -rf folder   # force delete (danger)
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πŸ”Ή 3. File Viewing

cat

πŸ‘‰ Show file content

cat file.txt
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less

πŸ‘‰ View large file (scroll)

less file.txt
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head / tail

πŸ‘‰ Show start/end of file

head file.txt
tail file.txt
tail -f log.txt   # live logs (VERY IMPORTANT)
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πŸ”Ή 4. Permissions & Ownership

chmod

πŸ‘‰ Change permissions

chmod 777 file.txt
chmod +x script.sh
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chown

πŸ‘‰ Change owner

sudo chown ubuntu file.txt
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πŸ”Ή 5. User Management

whoami

πŸ‘‰ Current user

whoami
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sudo

πŸ‘‰ Run as admin

sudo apt update
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πŸ”Ή 6. Package Management (Ubuntu)

apt

πŸ‘‰ Install/update packages

sudo apt update
sudo apt install nginx
sudo apt remove nginx
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πŸ”Ή 7. Process & System

ps

πŸ‘‰ Show processes

ps aux
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top

πŸ‘‰ Live system monitoring

top
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kill

πŸ‘‰ Stop process

kill 1234
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πŸ”Ή 8. Networking

ping

πŸ‘‰ Check connectivity

ping google.com
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curl

πŸ‘‰ Call API / URL

curl http://example.com
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ssh

πŸ‘‰ Connect to server

ssh ubuntu@ip-address
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πŸ”Ή 9. Disk & Storage

df -h

πŸ‘‰ Disk usage

df -h
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du -sh

πŸ‘‰ Folder size

du -sh *
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πŸ”Ή 10. Redirection & Output (VERY IMPORTANT)

echo

πŸ‘‰ Print text

echo "Hello"
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>

πŸ‘‰ Overwrite file

echo "Hello" > file.txt
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>>

πŸ‘‰ Append to file

echo "World" >> file.txt
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πŸ”Ή 11. Search & Text Processing

grep

πŸ‘‰ Search text

grep "error" log.txt
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find

πŸ‘‰ Find files

find . -name "file.txt"
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πŸ”Ή 12. Archive & Compression

tar

πŸ‘‰ Compress/extract

tar -cvf archive.tar folder/
tar -xvf archive.tar
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πŸ”Ή 13. History & Help

history

πŸ‘‰ Show commands history

history
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man

πŸ‘‰ Command manual

man ls
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πŸ”₯ MOST IMPORTANT (Tell your students)

If they remember only these β†’ they will survive:

ls
cd
pwd
mkdir
touch
cp
mv
rm
cat
tail -f
chmod
sudo
apt
grep
ssh
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