Appendix C. Arduino Quick Reference

Here is a quick explanation of all the standard instructions supported by the Arduino language.

For a more detailed reference, see the Arduino “Language Reference” page.


An Arduino sketch runs in two parts:

void setup()

This is where you set things up that have to be done once before the loop starts running, and then don’t need to happen again.

void loop()

This contains the main code of your sketch. It contains a set of instructions that get repeated over and over until the board is switched off.

Special Symbols

Arduino includes a number of symbols to delineate lines of code, comments, and blocks of code.

; (semicolon)

Every instruction (line of code) is terminated by a semicolon. This syntax ...

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