# Use of identifiers (e.g., Dn pin identifiers) **URL:** \ **Category:** Programming\ **Created:** [June 1, 2025, 1:43am UTC](https://forum.arduino.cc/t/use-of-identifiers-e-g-dn-pin-identifiers/1385966 "2025-06-01T01:43:34Z")\ **Posts on this page:** 1\ **Showing post:** 10
**Author:** ![grb](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/grb/32/1201129_2.png) [@grb](https://forum.arduino.cc/u/grb)\ **Post date:** [June 1, 2025, 4:57pm UTC](https://forum.arduino.cc/t/use-of-identifiers-e-g-dn-pin-identifiers/1385966/10 "2025-06-01T16:57:38Z")
> [@DrDiettrich](#): > > That's \*\*\*\*. D2 is different from 2. See the implementation of the D2 macro. Huh? I was asking a question, not expressing an opinion. In the [opening comment](https://forum.arduino.cc/t/use-of-identifiers-e-g-dn-pin-identifiers/1385966/2) by @ptillisch, the following advice was given: > [@ptillisch](#): > > So all this is to say that I strongly recommend against using the D_n_ pin names in your code. Therefore, this thread (which started as a side discussion in a different thread) [I was seeking](https://forum.arduino.cc/t/use-of-identifiers-e-g-dn-pin-identifiers/1385966/3) first to clarify the advice that was given by @ptillisch: > [@Low-level manipulation of LED matrix on UNO R4 WiFi](https://forum.arduino.cc/t/low-level-manipulation-of-led-matrix-on-uno-r4-wifi/1385939/8): > > > [@Low-level manipulation of LED matrix on UNO R4 WiFi](https://forum.arduino.cc/t/low-level-manipulation-of-led-matrix-on-uno-r4-wifi/1385939/8): > > > > So all this is to say that I strongly recommend against using the D_n_ pin names in your code. > > Interesting — until I read your comment, I would have assumed the opposite. So the preferred method to reference pin numbers is by their naked (unsigned integer) value? --- _[View the full topic](https://forum.arduino.cc/t/use-of-identifiers-e-g-dn-pin-identifiers/1385966)._