A Beginner's Arduino Guide/Where to get Arduino

There are several types of Arduino controllers:

Genuine Arduino Controllers
These controllers usually cost about $25 USD. Most of the funding goes to support the Arduino organization. We strongly encourage you to purchase at least one Genuine Arduino or make a contribution to the project.

Genuine controllers often work best with the Arduino software. They use common serial controller chips such as the FTDI chip that have certified signed drivers for both the PC and Mac.

Arduino Compatibles
Arduino compatibles are distinct from clones, in that they usually have distinct capabilities and significantly different hardware from official Arduino models. Arduino compatibles typically have their own branding, and don't try to pass themselves off as official Arduinos.

Here are some common features compatibles add or change compared to official Arduinos:
 * Different microcontroller (More power efficient, more powerful, different architecture, etc)
 * Different USB or serial port.
 * Solderless expansion connectors.
 * Built in Wireless radio for Wi-Fi, Bluetooth, etc.
 * Built in sensors.
 * Different formfactors.

Arduino Clones
Because Arduino is open source, there are a number of Arduino clones that simply use official designs with either no modification, or modifications exclusively for cost reductions. These clones are typically unbranded, though less scrupulous sellers may try to pass off counterfeits falsely labeled as official Arduino boards.

These are typically around $5, however you can find some Arduino Nano versions for as little as $2.27 (includes shipping). eBay is a popular place to purchase Arduino controllers, however be warned that many of the suppliers are in Hong Kong and China, and shipping times can be longer then usual. Allow one or two weeks for shipping at a minimum. Don't be shocked if a clone unit is a dud or acts funky - it comes with the territory.

The lower-cost Arduino Clones use a lower-cost serial interface chip such as the CH340D. The drivers for these chips are not included in the Arduino IDE. You must install these drivers manually.