Double precision floating point number. Occupies 4 bytes.
The double implementation on the Arduino is currently exactly the same as the float, with no gain in precision.
Users who borrow code from other sources that includes double variables may wish to examine the code to see if the implied precision is different from that actually achieved on the Arduino.
Corrections, suggestions, and new documentation should be posted to the Forum.
The text of the Arduino reference is licensed under a Creative Commons Attribution-ShareAlike 3.0 License. Code samples in the reference are released into the public domain.