Recommended · for beginners
How To Test Amperage / Amp Draw and properly measure and fuse a circuit
Why people recommend it
Pointed to as a basic demonstration of measuring current with a multimeter, placing the meter in series so you can read a load's actual draw.
Watch for: Amps mode goes in series, never across the supply
In their words
There will be lots of web pages about measuring amps with a meter, here is one.
Nick Gammon on arduino.stackexchange.com, Apr 2017. CC BY-SA.