Linux for Beginners

Linux, strictly speaking, is the kernel: the core program that manages hardware, memory, processes and files. A distribution such as Ubuntu, Fedora or Linux Mint bundles that kernel with a shell, command-line tools, a package manager, default settings and usually a graphical desktop.

The terminal is the window that shows text and passes your keystrokes on. The shell is the program running inside it, usually bash, which reads your command and starts the right tool. A display glitch is a terminal problem; a 'command not found' message comes from the shell.

Pick a popular, well documented distribution with a long-term support release, such as Ubuntu LTS or Linux Mint, and start learning. Skills transfer between distribution families almost entirely; mostly the package manager changes, for example apt on Ubuntu and dnf on Fedora.

A prompt like alex@laptop:~$ means user alex, on the computer named laptop, currently in the home folder (~). The dollar sign marks a normal user. If the prompt ends in # instead, you are the root administrator and should be extra careful.

Not for the first lesson. Later you can use a virtual machine, WSL on Windows or a Live-USB. A virtual machine is the safest option for most beginners because nothing on your real disk is touched and snapshots let you roll back mistakes.