Previously referred to as Raspbian, the Raspberry Pi OS is the official operating system for the Raspberry Pi board. It’s based on the Debian distribution and comes packed with more than 35,000 software packages for you to enjoy. There are three versions of the Raspberry Pi OS you can choose from: the desktop version, desktop with recommended software, and Lite (no desktop user interface, only a command line). All the versions are specifically optimized to work on your Raspberry Pi board, so no need to worry about running into compatibility issues.
Since the Raspberry Pi OS was developed by the Raspberry Pi Foundation itself, it comes as no surprise that this is also the easiest OS to install. You simply have to download the OS installer app called Raspberry Pi Imager (also made by the foundation), insert your microSD card into your computer, and select your preferred version of the Raspberry Pi OS from the list.
Ease of installation aside, the Raspberry Pi OS is a great operating system for Raspberry Pi beginners because it’s multi-purpose. If you’re a developer, you can use it to install whatever software you need to create your program. You can even connect hardware like sensors and Arduino microcontrollers to the GPIO pins and ports, and there’s a good chance they will be recognized without issues. If you’re not a developer, you can simply use the board as any old computer. You can browse the internet, play music, write documents, and watch videos.