Google's Gmail Web-based email service runs on the Internet Message Access Protocol system, but it also offers Post Office Protocol mail server access.
Definition of LUMEN. 1. 2. : the bore of a tube (as of a hollow needle or catheter). 3. : a unit of luminous flux equal to the light emitted in a unit solid angle by a uniform point source of one candle intensity.
Lumen is a unit of light, which is also known as Luminous flux. Lumens (LM) are a measurement unit, which tells what the total amount of light emitted from a flashlight or headlamp. You can roughly say that the more Lumens the brighter the light. When we test and compare our products, we use Lumens to see the total amount of light output.