4.2 | 233 Votes
What is an INO file?
The Arduino electronics prototyping platform allows developers to create and install basic programs, called sketches, on a variety of specialized circuit boards. Sketches can perform simple functions, such as making an LED installed on a circuit board blink, or complex functions, such as transmitting data over the internet. Developers create Arduino sketches in the Arduino Integrated Development Environment (IDE), which saves sketches as INO files.
Prior to Arduino 1.0, the Arduino IDE saved sketches as .PDE files. While developers can still open PDE files in Arduino, they should now save sketches (including those previously saved as PDE files) as INO files.
How to open an INO file
INO files are meant to be opened and edited in the Arduino Integrated Development Environment (multiplatform). To open an INO file in Arduino, select File → Open from the program's menu bar.
Because INO files are plain text files, you can also open them in any text editor, including: