# Linux101 References * [Linux101 Course](https://academy.tcm-sec.com/p/linux-101) * [TCM Linux101-Resources](https://github.com/beskridge/Linux101-Resources) - by Brent Eskridge * [Supplementary exercises](https://github.com/beskridge/Linux101-Resources/blob/main/exercises.md) ## Introduction * [Linux Distributions Timeline](https://upload.wikimedia.org/wikipedia/commons/1/1b/Linux_Distribution_Timeline.svg) * [Ubuntu](https://ubuntu.com/) * [Kali](https://www.kali.org/) * [ParrotOS](https://www.parrotsec.org/) * [VirtualBox Ubuntu Installation](https://ubuntu.com/tutorials/how-to-run-ubuntu-desktop-on-a-virtual-machine-using-virtualbox#1-overview) ## Command Line basics * [The Linux *man-pages* project](https://www.kernel.org/doc/man-pages/) * [Explain-Shell](https://explainshell.com/) * [Shell-How](https://www.shell.how/) * [Command-not-found](https://command-not-found.com/) * [ls](https://linuxize.com/post/how-to-list-files-in-linux-using-the-ls-command/) * [less](https://linuxize.com/post/less-command-in-linux/) * [cat](https://linuxize.com/post/linux-cat-command/) * [Bash Aliases](https://linuxize.com/post/how-to-create-bash-aliases/) ## Files and the Filesystem * [Filesystem Hierarchy Standard](https://refspecs.linuxfoundation.org/FHS_3.0/fhs/index.html) * [FHS - Wikipedia](https://en.wikipedia.org/wiki/Filesystem_Hierarchy_Standard) * [df](https://linuxize.com/post/how-to-check-disk-space-in-linux-using-the-df-command/) * [du](https://linuxize.com/post/du-command-in-linux/) * [Size of a directory](https://linuxize.com/post/how-get-size-of-file-directory-linux/) * [Absolute vs Relative Path](https://linuxhandbook.com/absolute-vs-relative-path/) * [cp](https://linuxize.com/post/cp-command-in-linux/) * [rm](https://linuxize.com/post/rm-command-in-linux/) * [Shell Expansions](https://www.gnu.org/savannah-checkouts/gnu/bash/manual/bash.html#Shell-Expansions) * [tail](https://linuxize.com/post/linux-tail-command/) * [diff](https://linuxize.com/post/diff-command-in-linux/) * [Soft Link And Hard Link](https://ostechnix.com/explaining-soft-link-and-hard-link-in-linux-with-examples/) * [tar](https://linuxize.com/post/how-to-create-and-extract-archives-using-the-tar-command-in-linux/) * [gzip](https://linuxize.com/post/gzip-command-in-linux/) * [find](https://linuxize.com/post/how-to-find-files-in-linux-using-the-command-line/) * [which](https://linuxize.com/post/linux-which-command/) * [locate](https://linuxize.com/post/locate-command-in-linux/) ## Users and Groups * [UID](https://linuxhandbook.com/uid-linux/) * [who](https://linuxize.com/post/who-command-in-linux/) * [/etc/passwd](https://linuxize.com/post/etc-passwd-file/) * [/etc/shadow](https://linuxize.com/post/etc-shadow-file/) * [/etc/group](https://linuxize.com/post/how-to-list-groups-in-linux/) * [Linux File Permissions](https://linuxize.com/post/understanding-linux-file-permissions/) * [chmod](https://linuxize.com/post/chmod-command-in-linux/) * [chmod Calculator](https://nettools.club/chmod_calc) * [chown](https://linuxize.com/post/linux-chown-command/) * [sudo](https://linuxize.com/post/sudo-command-in-linux/) * [passwd](https://linuxize.com/post/how-to-change-user-password-in-ubuntu/) * [root password](https://linuxize.com/post/how-to-change-root-password-in-ubuntu/) ## Installing Software * [Deb Packages install](https://linuxize.com/post/how-to-install-deb-packages-on-ubuntu/) * [apt](https://linuxize.com/post/how-to-use-apt-command/) * [Rpm Packages install](https://linuxize.com/post/rpm-command-in-linux/#) * [yum](https://linuxize.com/post/how-to-install-updates-on-centos/) * [gcc](https://linuxize.com/post/how-to-install-gcc-on-ubuntu-20-04/) * [checkinstall](https://help.ubuntu.com/community/CheckInstall) ## Shell basics * [Common Shells](https://www.tecmint.com/different-types-of-linux-shells/) * [Bash](https://www.gnu.org/software/bash/manual/bash.html) * [zsh](https://www.zsh.org/) * [Oh My Zsh](https://ohmyz.sh/) * [Learn Shell](https://www.learnshell.org/) * [Environment Variables](https://linuxize.com/post/how-to-set-and-list-environment-variables-in-linux/) * [Bash Startup Files](https://www.gnu.org/software/bash/manual/html_node/Bash-Startup-Files.html) * [Bash Write to File](https://linuxize.com/post/bash-write-to-file/) * [History](https://linuxize.com/post/history-command-in-linux/) ## Utilities and File editors * [grep](https://linuxize.com/post/how-to-use-grep-command-to-search-files-in-linux/) * [Regex in Grep](https://linuxize.com/post/regular-expressions-in-grep/) * [sort](https://www.geeksforgeeks.org/sort-command-linuxunix-examples/) * [wc](https://linuxize.com/post/linux-wc-command/) * [sed](https://linuxize.com/post/how-to-use-sed-to-find-and-replace-string-in-files/) * [sed Manual - gnu.org](https://www.gnu.org/software/sed/manual/sed.html) * [awk](https://linuxize.com/post/awk-command/) * [awk Manual - gnu.org](https://www.gnu.org/software/gawk/manual/gawk.html) * [tr](https://linuxize.com/post/linux-tr-command/) * [ping](https://linuxize.com/post/linux-ping-command/) * [ifconfig](https://linuxize.com/post/ifconfig-command/) * [ip](https://linuxize.com/post/linux-ip-command/) * [Listening Ports](https://linuxize.com/post/check-listening-ports-linux/) * [scp](https://linuxize.com/post/how-to-use-scp-command-to-securely-transfer-files/) * [rsync](https://linuxize.com/post/how-to-use-rsync-for-local-and-remote-data-transfer-and-synchronization/) * [rsync over SSH](https://linuxize.com/post/how-to-transfer-files-with-rsync-over-ssh/) * [file](https://linuxize.com/post/linux-file-command/) * [nano editor](https://www.nano-editor.org/docs.php) * [nano usage](https://linuxize.com/post/how-to-use-nano-text-editor/) * [nano keyboard shortcuts](https://cheatography.com/bipinthite/cheat-sheets/nano-editor/) * [vim](https://linuxize.com/post/how-to-save-file-in-vim-quit-editor/) * [vim help files](https://vimhelp.org/) * [vim cheat sheet](https://cheatography.com/typo209/cheat-sheets/comprehensive-vim-cheat-sheet/) ## Process Management * [ps](https://linuxize.com/post/ps-command-in-linux/) * [pstree](https://linuxize.com/post/pstree-command-in-linux/) * [top](https://www.geeksforgeeks.org/top-command-in-linux-with-examples/) * [htop](https://www.geeksforgeeks.org/htop-command-in-linux-with-examples/) * [jobs-fg-bg Background processes](https://linuxize.com/post/how-to-run-linux-commands-in-background/) * [Zombie Process](https://totozhang.github.io/2016-01-16-linux-zombieprocess/) * [Kill a Process](https://linuxize.com/post/how-to-kill-a-process-in-linux/) * [kill](https://linuxize.com/post/kill-command-in-linux/) * [pkill](https://linuxize.com/post/pkill-command-in-linux/) * [sleep](https://linuxize.com/post/how-to-use-linux-sleep-command-to-pause-a-bash-script/) * [crontab.guru](https://crontab.guru/) * [crontab](https://linuxize.com/post/scheduling-cron-jobs-with-crontab/) * [List cron jobs](https://linuxize.com/post/how-to-list-cron-jobs-in-linux/) * [Linux Run Levels](https://likegeeks.com/linux-runlevels/) * [Ubuntu Bootup](https://help.ubuntu.com/community/UbuntuBootupHowto) ## Regular Expressions * [grep Regular Expressions](https://linuxize.com/post/regular-expressions-in-grep/) * [grep regex examples](https://www.cyberciti.biz/faq/grep-regular-expressions/) * [Online RegExr tool](https://regexr.com/) * [Regex101 tool](https://regex101.com/) * [Cyrilex tool](https://extendsclass.com/regex-tester.html) * [EmailRegex Examples](https://emailregex.com/) ## Bash Scripting * [Bash Shell Scripting - Wikibooks](https://en.wikibooks.org/wiki/Bash_Shell_Scripting) * [shebang](https://en.wikipedia.org/wiki/Shebang_\(Unix\)) *** --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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