Table of contents
Linux Commands
| Commands | Definition |
| ls | List the files and directories in the current directory. |
| ls -a | List all the files or directories including hidden files. |
| cd | Change the current directory. For example, "cd ubuntu" will move you into the "ubuntu" directory. |
| pwd | Print the working directory, which shows you the path of the current directory. |
| mkdir | Create a new directory. For instance, "mkdir abc" will create a directory named "abc" |
| touch | Create an empty file. For example, "touch text1.txt" will create a file named "text1.txt" |
| touch file{1...5}.txt | Creates multiple empty files. For example, file1.txt, file2.txt, file3.txt, file4.txt, file5.txt |
| rm <filename> | Deletes a single file. For example, "rm text1.txt" will delete the "text1.txt" file. |
| rm -r <foldername> | Deletes the folder and all the files within the folder. (r-recursively) |
| rm -rf <foldername> | Deletes the folder and all the files within the folder without any prompt. (r-recursive, f-forcefully) |
| cp | Copy files or directories. For instance, "cp text1.txt /path/to/destination" will copy "file.txt" to the specified destination. |
| mv | Move or rename files or directories. For example, "mv text1.txt new_location/" will move the file to the "new_location" directory. |
| cat | Display the contents of a file on the terminal. For instance, "cat text1.txt" will show the content of "text1.txt." |
| echo | Print text to the terminal. For example, echo "Hello, Linux!" will display "Hello, Linux!" on the screen. |
| grep <keyword> <pathOfFile> | Search for a specific string in a file. For instance, grep "keyword" text1.txt will find lines containing the "keyword" in "file.txt." |
| grep -i <keyword> <pathOfFile> | Search for a specific string in a file insensitively. |
| grep -ir <keyword> <pathDirectory> | Search recursively for a string in the directory |
| grep -c <keyword> <pathfile> | Displays the count of the number of matches |
| man | Access the manual pages for commands. For example, "man ls" will show the manual for the ls command. |
| sudo | Execute a command with superuser (administrator) privileges. Be careful when using "sudo" as it allows you to make changes that can affect the system. |
| mkdir -p | Create a nested directory A/B/C/D/E. For instance, "mkdir -p A/B/C/D/E" creates a nested directory A/B/C/D/E. (p-parent directory) |
| date | Displays the system date and time |
| clear | Clears the terminal |
| whoami | Shows the current user |
| crontab -l | Lists the crontab entries |
| crontab -e | Opens the crontab editors |
| sudo <user> | Switchs to the given user |
| sudo cat /etc/passwd | Shows all the users inside the system |
| sudo useradd <username> | Creates a new user |
| sudo cat /etc/group | Shows all the groups inside the system |
| sudo groupadd <groupname> | Creates a new group |
| sudo usermod -aG <groupname> <username> | Adds a user to a particular group |
| sudo gpasswd -M <user1>, <user2>, <user3>, <user4> <groupname> | Adds a multiple user to a particular group (M-multiple) |
| sudo gpasswd -d <user> <group> | Deletes a user from a particular group (d-delete) |
| sudo groupdel <groupname> | Delete a particular group |
| chmod [permission] <filename> | Change the access mode of a file(Permissions: r-read,w-write,x-execute) |
| ssh -keygen | Generates a connection in between public and private key |
| find <typeOfFile> | find files and directories |
| history | Shows the history of all commands used |
| vim <filename.txt> | Created and opens a text editor |
| head -n <filename> | Shows starting 2 records of the file |
| tail -n <filename> | Shows the last 2 records of the file |
| exit | Exits from the user |
| sudo apt update | Update the packages |
| sudo apt upgrade | Upgrade the packages |
| sudo apt install <packageName> | Install the packages |
| sudo apt purge <packageName> | Uninstall the packages |
Git Commands
| Commands | Description |
| git init | Initializes an empty repository |
| git status | Displays the state of the working tree and staging area. Shows the tracked, untracked, staged, unstaged file and changes |
| git add <fileName> | Adds new or changed files to the Git staging area |
| git commit -m "Message" | Moves the file from staging area to the local working directory (m-message) |
| git rm --cached <filename> | Remove one or many files from the Git index but keeps the file in the working area (rm-removes) |
| git rm <filename> | Remove one or many files from the Git index and also from the working area (rm-removes) |
| git restore <filename> | Restores the deleted files |
| git log | Displays the most recent commits with commit id and the status of the head |
| git log --oneline | Displays only the commit id and the commit message |
| git log --oneline --pretty | Same as git log except commit id is shortened |
| git config --global user.name="username" | Setting the Git username globally on your computer |
| git config --global user.name="email" | Setting the Git email globally on your computer |
| git checkout -b <branchName> | Creates a new branch with <branchName> and switch to the created branch |
| git checkout <branchName> | Switch to the given branch |
| git branch | Shows all the existing branch. The current branch is shown in green color. |
| git clone url | Copies the github repository to local |
| git remote -v | Shows the remote url of the current repository |
| git pull origin <branchName> | Pull the changes of the origin branch to the branch we are checked out in |
| git push origin <branchName> | Pushes the changes of the local branch to the origin branch |
| git remote set-url origin <newurl> | Sets the URL for existing remote repository |
| git remote set-url [--push] origin <newurl> | Updates the push URL with the <newurl> |
| git remote set-url --add origin <newurl> | Adds the <newurl> of the remote repository in local |
| git remote set-url --delete origin <oldurl> | Deletes the <oldurl> of the remote repository in local |
| git revert | Reverts the changes but maintains the version history by creating a new commit |
| git reset | Reverts the changes and do not maintain the version history |
| git merge <branchName> | Merges one branch to another |
| git rebase | Merge the branch in a linear manner |
| git stash | Stores the changes into the working directory without actually committing the file. |
| git stash pop | Bring back the stashed file to the current working directory |
| git cherry-pick <commitid> | Applies any specific commit to any other branch. |
Hope this cheat sheet would be useful! Thanks for reading!
~Shilpi