Ubuntu

Ubuntu is a ready system on the Linux kernel. Programs are packaged with apt. Long-term support releases, such as 22.04 and 24.04, are chosen for servers. It is not a programming language: a language and a tool are installed on top of it.

Ubuntu is one of the most common Linux systems for a development machine and a server.

• A machine for a web server
• Installing Docker and Nginx
• Installing a program with apt
• Entering a remote server with SSH

On Ubuntu you install a package from the terminal, change a file permission, and start or stop a service with systemd. The desktop release also has a window environment. The server release has no windows. The work is on the command line.

The first day on desktop Ubuntu is easy. The difficulty starts with the terminal, permissions, and services. sudo is not needed for every command. It is used only when the system itself changes.

Advantage: it is free, there are many packages, and server documentation is plentiful. Limit: some closed desktop programs and games are for Windows. Mixing an LTS release with a short one can break an upgrade.

A package source is a repository. apt refreshes the list and installs a package. A service runs in the background with systemd.

• An LTS release gets updates for years
• root is the highest user
• sudo gives that right to one command
• /etc is the place for config files

These commands refresh the package list and install Nginx. On a server, run this only when you need it.

sudo apt update
sudo apt install -y nginx

• Are Ubuntu and Linux the same? Linux is the kernel. Ubuntu is a distribution built with that kernel.
• Is Ubuntu free? Yes. Private support can be sold separately.
• Does a Windows program open on Ubuntu? Usually no. You need a build made for Linux.