It has 14 digital pins and 6 analog pins, giving you a total of 20 GPIO pins available for your project. The entry price point isn’t too high but you still get ample ports for most projects in a relatively compact package. Arduino is a microcontroller board based on the ATmega328P.
If you’re a beginner trying to get into the world of Arduino, Uno is the most ideal option to go for. The three most commonly used Arduino versions are - Uno, Nano and Mega. There are various versions of Arduino available, each having its own advantages and use cases whether it’s in terms of shape, size or the number of inputs and outputs. It is powered by an ATMega328P microcontroller and is the most popular choice among the community because it’s cheap, easy to learn and use, and also a variety of premade modules are available for this which makes it easier for developing new projects or prototypes.
Arduino is a popular open-source hardware platform that is easy to use for beginners, yet flexible enough for advanced users.