1.pwd – Print Working Directory:
Example: Display the current working directory.
command: pwd
Output: /home/your_username
2.ls – List Files and Directories:
Example: List files and directories in the current directory.
command: ls
Output:
file1.txt file2.txt directory1 directory2
3.cd-Change Directory:
Example: Change to the home directory.
command: cd ~
Now you re in the home directory.
4.mkdir-Make Directory:
Example: Create a new directory named “documents”.
command: mkdir documents
5.touch -Create Empty File:
Example: Create a new empty file named “example.txt”.
command: touch example.txt
6.cp-Copy Files or Directories:
Example: Copy a file from one location to another.
command: cp sourcefile destination
example : cp example.txt documents/
7.mv-Move (Rename) Files or Directories:
Example: Move a file to a different location or rename it.
mv oldfile newfile
mv example.txt newlocation/
8.rm-Remove Files or Directories:
Example: Delete a file named “unwanted.txt”.
rm unwanted.txt
9.cat-Concatenate and Display File Content:
Example: Display the contents of a file named “example.txt”.
cat example.txt
Output:
This is the content of example.txt.
10.man– Display Manual Pages:
Example:Get information about the ls command.
command : man ls
(Use arrow keys to navigate, press q to exit)
11.grep -Search Text in Files:
Example: Search for the word “error” in a log file.
command: grep “error” logfile.txt
12.find-Search for Files and Directories:
Example:Find all .txt files in the current directory and its subdirectories.
command: find . -name ” .txt”
13.ps-Display Information about Running Processes:
Example: List all running processes.
ps aux
14.kill-Terminate a Process:
Example: Terminate a process with a specific process ID.
kill -9 <process_id>
15.chmod-Change File Permissions:
Example: Give read and write permissions to the owner of a file.
chmod u+rw filename
16.df-Display Disk Space Usage:
Example: Show disk space usage for all mounted filesystems.
df -h
17.du -Display File and Directory Space Usage:
Example: Show the sizes of directories in the current location.
du -h –max-depth=1
18.tar – Create or Extract Tarballs:
Example: Create a compressed tarball of a directory.
tar -czvf archive.tar.gz directory/
19.ssh-Secure Shell:
Example:Connect to a remote server.
ssh username@remote_server
20.top-Display System Activity in Real Time:
Example: Display real-time information about CPU and memory usage.
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