Choosing an Arduino for Your Project
jimblom, 
bboyho Introduction
Are you just looking for specs between Arduino boards?
Check out our Arduino Comparison Guide! We've compiled every Arduino development board we carry, so you can quickly compare them to find the perfect one for your needs.
Let's face it, there are a a lot of different Arduino boards out there. How do you decide which one you need for your project? In this tutorial, we'll take a look at the diverse world of Arduino boards. We'll delve deeper into each board, examining the pros, cons, and example use-cases.
Arduino is an open-source electronics prototyping platform based on flexible, easy-to-use hardware and software. It's intended for artists, designers, hobbyists, and anyone interested in creating interactive objects or environments. Or more simply, you load on some code and it can read sensors, perform actions based on inputs from buttons, control motors, and accept shields to further expand it's capabilities. Really, you can do almost anything.
All Arduino boards have one thing in common: they are programmed through the Arduino IDE. This is the software that allows you to write and upload code. Beyond that, there can be a lot of differences. The number of inputs and outputs (how many sensors, LEDs, and buttons you can use on a single board), speed, operating voltage, and form factor are just a few of the variables. Some boards are designed to be embedded and have no programming interface (hardware) which you would need to buy separately. Some can run directly from a 3.7V battery, others need at least 5V.
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If you don't know what Arduino is but found yourself here, you may want to start with our What is an Arduino tutorial?.
What is an Arduino?
You should also have a good understanding of the Arduino IDE. If you need help installing it, visit this tutorial.