Why does the guide suggest powering the LDR using the output from A5? Shouldn’t the output of the 3.3V pin be just as steady? I’m assuming that sourcing the current for the LED from D0 is just because the 3.3V pin is on the other side of the board and no wires are included in the kit. Thanks.
If you use an IO pin, you can also turn the attached ‘thing’ off, which might be beneficial in certain cases (like turning off an LED, or saving power on an unused sensor)
Providing a link to "that guide" might be good practice.
“That guide” is the official guide. Anyway…
Based on Moors7 response I’m going with connecting the LDR to A5 is just a personal design decision. It could just as well be the 3.3V pin.
BTW I’m trying to clarify some points for a workshop I’m doing this Saturday. 20 people! and I know someone will ask me that.
However, thanks for that Moors7. Nice trick for saving a little bit of power at the expense of a pin.