Key Terminlogy you need to know @ Linux Guide:

1. Sudo: It is short for "susbsitute user do". It grants the user temporaily prilavged access throughout the system.
2. Package Manager(s): A package manager is a utility designed to assist with common actions taken when installing, updating, and removing packages. Regular functions of a package manager may include: Installing, Removing and updating packages.
3. Command Line Interface: A Command Line Interface (CLI) is a text-based user interface (UI) used to interact with a computer program or operating system. Through the CLI, users type commands to navigate, run programs, or configure the system.
4. Display Manager: It is also known as a Login Manager. It is typically a graphical user interface (GUI) that is displayed at the end of the boot process in place of the default shell interface. This typically allows you to login with your password to you account.
5. Graphical User Interface: Also known as a GUI! Is another way of users interacting with their deivces through icons and visual indicators.
6. Free Open Source Software: Also known as FOSS! Is software that is available under a license that grants the right to use, modify, and distribute the software, modified or not, to everyone free of charge.
7. Linux: Linux in itself refers to two things, the former being the kernel itself developed by Linus Torvalds. Or the family of opreating systems that use the Linux Kernel.
8. Window Manager: A window manager is a piece of system software for X that controls the placement of windows within a Graphical User Interface (GUI). It controls several features of the GUI, such as the borders, title bar, size, and the ability to resize the windows. It can be provided as a part of the desktop environment.

More coming soon in future updates.