Hello everyone I'm your friend JamesBin, this text allows you to learn from arduino 0 and 1, let's start learning!
First, know arduino
Arduino The name comes from the Italian, which was intended as a "strong friend", was born in Italy in 2005, the Interaction Design Institute Ivrea (Interaction Design Institute Ivrea), one of the main founders of the leading project named Massimo Banzi.
Arduino projects created original intention was to reduce the threshold of Interaction Design Institute in the creation of interactive works of students. Which in addition to reducing student costs, it also takes into account the difficulty of learning. In other words, as long as it takes very little money, with very little programming knowledge, you can abstract ideas, create different works.
The spirit of openness, so that more fans to benefit, at the beginning of Arduino project created to comply with the open-source hardware protocol, anyone can get free hardware design drawings Arduino board, and according to their own design process mass production.
In recent years with the rise of intelligent hardware, the rise of the world called maker culture of fashion, they use Arduino and its surrounding various hardware modules to quickly build all kinds of fun products. For example, you can quickly create personalized air quality detectors, fire alarms, and even cat friends make intelligent feed the cat, a small robot can even make all kinds of strange, flight enthusiasts have designed a variety of aircraft and ultimately complete a variety of thrilling aerial.
Since Arduino can make so many interesting things, then let us know about her! 
Source: Arduino UNO board
Source: Arduino UNO board
shown above, Arduino the base circuit board called Arduino UNO. The board was originally September 25, 2011 issued by the General Assembly in New York on maker culture (New York Maker Faire), the model name "UNO", is the Italian "a" means.
Brief summary, the circuit board consists of three parts:
- processor
- Power Interface
- Expansion Slots
The processor used is produced by Atmel processor.
There are three power supply mode, the first one is directly powered directly through the USB interface, the second is powered by a cylindrical external power interface, the last one is powered by extending pins 3V or 5V on the socket.
Expansion slots are divided into analog and digital signal pin and signal pin ground pin. As the name suggests, a digital signal or an output pin can be introduced directly into a digital signal, an analog signal or output pin is introduced into an analog signal. When the complex circuit design time can access the extended expansion slot plate, according to different needs, the entire board be extended to enhance the scalability of the base circuit board. FIG Reset button can restart the operation of the entire circuit board.
