This is something that I’ve been asked several times, usually by people who aren’t into electronics. The thing is, the people who have asked me are almost always really into making/crafts or DIY, or something similar…things that Arduino is just great for! There are lots of other microcontrollers, too, such as the ESP8266, which is still one of my favorites, but for most people, all of these things fall under the broad category of “Arduino” which, though inaccurate, does serve as a fairly simple “category” to lump everything in to.
So what is it? First, I’m going to provide a few links:
This will kind of get you familiar with what it is, physically, and with some research, most of it’s capabilities.
The thing about Arduino, and its many spinoffs and copycats, is that the limitations are becoming less and less. What is Arduino? Basically it’s a microcontroller board that you can program in a rather nice IDE to control and get information from just about any kind of electronics you want to. Hook up sensors, buttons, screens, knobs, lights…you can handle just about anything with a basic Arduino unit, like the Uno.
But…there’s a lot more to it than that.
Arduino is more of a community than a single board, or even a brand name at this point. People and companies develop and iterate on their own (and other people’s) developments over and over, and most of it is open sourced. These boards are built with parts that, generally, can be bought and used off the shelf, no special lots or anything. And they’re built with a huge variety of form factors, voltage requirements, numbers of pins, amount of memory, and additional capabilities. Some do WiFi. Some have Bluetooth built in. Some have expandable memory via microSD cards. And all of them can have all of these capabilities added!
You can buy sensors of all sorts and add them to your project. You can buy all sorts of form-factors, so that your project can fit in a box, or be wearable, or mountable on the wall or ceiling. You can build waterproof projects, or pumps. Pretty much anything.
And that is what Arduino is. Pretty much anything that you can think of. If you’re willing to do the research (and then acquire the parts that you need, and the skills to put them together, of course) then you can build anything that you want. Arduinos are controllers, which means that they can control much more powerful things, even though they themselves are overall quite small and low-powered.
Arduino is for electronics what the 3D printer is for plastics manufacturing. Something that allows people at the home/hobbyist level to create and make their ideas, with no huge startup costs or ordering massive lots of parts. No real special training, even, just the ability and desire to read, experiment, and expand their knowledge.