Arduino is a open source circuit board, it belongs to MCU (micro computer unit). Arduino makes it convenient to design a circuit for it has unit lots of chip, capacitance, resistance and other electrical components on it. We used to combined a circuit with electric soldering iron, bread board and the electrical components. It’s not convenient to connect a circuit with so many electrical components.

Arduino has the feature of having much I/O port to connect the external circuit, uniting kinds of electrical components to simplify user’s operation.

Arduino has several generation such as: Arduino Uno, Arduino zero, Arduino Mega2560 and so on. Arduino has two types communicate port: digital port and analog port. Actually, all of these ports are digital I/O port. However, the digital port has several pin of PWM (pulse-width modulation), for the use of PWM, the pulse it outputs may looks like analog signal, but it’s just look like analog signal. Note that the analog port can’t be used to output analog signal. It’s used to communicate with external circuit through input analog signal. There’s a feature that the pin 13 connects to a led for showing the display of circuit. It has already connected to the power in the Arduino, so, just as you know, when output logic is low, the led will light, or the led will off.

Developer also designed a special programming software for Arduino: Arduino IDE. IDE is specially designed for Arduino, you can use C or Java to program it. Arduino IDE can run in Windows, Macintosh OS X and Linux system. It’s so compatible to these main system. Most MCU can only be developed on the Windows operate platform.

What can we do with the Arduino?  

As Arduino has already combined much electrical components, we could connect a sensor to the analog port. Then it can detect the surrounding environment, or connect to a motor shield. The motor will turn around. The simplest circuit is connected to a led, then program the Arduino IDE to flash the led. So you can do almost everything using Arduino.