Is written in C\C++ C/C++ It is written in C/C++ in simplified manner.
Arduino hardware is an open-source circuit board with a microprocessor and input/output (I/O) pins for communication and controlling physical objects (LED, servos, buttons, etc.). The board will typically be powered via USB or an external power supply which in turn allows it to power other hardware and sensors. Arduino also has an open-source software component which is similar to C++. Netduino. The Netduino is the cousin of the Arduino. It is still an open source hardware hacking and prototyping solution. But the Netduino runs .NET Micro Framework for its software base. Of course the arduino can run any language there is a complier for, but it can interpret any code that someone bothers to write an interpreter for it. I have not researched this. I just recommended sticking with the standard c/c++ enviroment, and noted that with communications the pc could run a pc language. I would stick with the c/c++ arduino enviroment for the arduino. Java, Python, Processing are used on the pc to run communications with the arduino, they are not laguages up vote 5 down vote. The Arduino language is C++, but it is very different from most C++ varieties. The Arduino language has a lot of abstraction built in, especially in the hardware interfaces, which makes it very simple to use. If you have a background in Java, C and C++ should be very similar. In fact many of the libraries are written in C++. Much of the underlying system is not object oriented, but it could be. Thus, The arduino language is C++ or C. C++ is not garbage collected. At a conceptual level, when using the Arduino software stack, all boards are programmed over an RS-232 serial connection, but the way this is implemented varies by hardware version. Serial Arduino boards contain a level shifter circuit to convert between RS-232-level and TTL-level signals. An official Arduino Uno with descriptions of the I/O locations. An early Arduino board with an RS-232 serial interface (upper left) and an Atmel ATmega8 microcontroller chip (black, lower right); the 14 digital I/O pins are located at the top and the six analog input pins at the lower right. The Arduino consist of a microcontroller (the ATmega328on the UNO version). So the Arduino is a PCB with the pins of the microcontroller nicly separated, a powersuply, a crystal and the FTDI for the USB connection with a on-board firmware so you can easly programm it with its own IDE.  Arduino is an open source electronics platform accompanied with a hardware and software to design, develop and test complex electronics prototypes and products. The hardware consists of a microcontroller with other electronic components which can be programmed using the software to do almost any task. As the program written in C\C++ is named as Project, in the same way the code written in Wiring (even in Processing and Arduino) is termed as Sketch. The name sketch gives a familiar look for an artist. Arduino and Arduino-compatible boards use printed circuit expansion boards called shields, which plug into the normally supplied Arduino pin headers. Shields can provide motor controls, GPS, Ethernet, LCD, or breadboarding (prototyping). A number of shields can also be made DIY. An official Arduino Uno with descriptions of the I/O locations. An early Arduino board with an RS-232 serial interface (upper left) and an Atmel ATmega8 microcontroller chip (black, lower right); the 14 digital I/O pins are located at the top and the six analog input pins at the lower right. Arduino is an open-source computer hardware and software company, project and user community that designs and manufactures microcontroller-based kits for building digital devices and interactive objects that can sense and control the physical world. An official Arduino Uno with descriptions of the I/O locations. An early Arduino board with an RS-232 serial interface (upper left) and an Atmel ATmega8 microcontroller chip (black, lower right); the 14 digital I/O pins are located at the top and the six analog input pins at the lower right. The arduino language is really great for beginners, but have some limitations (e.g. you must have all your files in the same folder). And it is basically a simplification of C/C++ (you can practically copy&paste arduino code to a C/C++ file, and it will work). In fact many of the libraries are written in C++. Much of the underlying system is not object oriented, but it could be. Thus, The arduino language is C++ or C. C++ is not garbage collected. The Arduino integrated development environment (IDE) is a cross-platform application written in Java, and derives from the IDE for the Processing programming language and the Wiring projects. It is designed to introduce programming to artists and other newcomers unfamiliar with software development. An official Arduino Uno with descriptions of the I/O locations. An early Arduino board with an RS-232 serial interface (upper left) and an Atmel ATmega8 microcontroller chip (black, lower right); the 14 digital I/O pins are located at the top and the six analog input pins at the lower right.
http://www.howtogeek.com/65963/what-is-arduino/ http://electronics.stackexchange.com/questions/13616/which-programming-languages-are-supported-to-program-arduino http://arduino.stackexchange.com/questions/816/c-vs-the-arduino-language https://en.wikipedia.org/wiki/Arduino http://electronics.stackexchange.com/questions/99434/arduino-vs-microprocessor-vs-microcontroller http://www.engineersgarage.com/articles/arduino https://en.wikipedia.org/wiki/Arduino https://en.wikipedia.org/wiki/Arduino http://arduino.stackexchange.com/questions/816/c-vs-the-arduino-language https://en.wikipedia.org/wiki/Arduino
what is arduino written in