CFM/SCFM?
Cubic Feet per Minute/Standard Cubic Feet per Minute. These terms can refer to at least two things when it comes to air compressors:
The volume of air that an air compressor delivers over time (minutes)
The volume of air that an air tool consumes when in use (its demand).
The "Standard" in SCFM refers to standard conditions of atmospheric pressure, temperature, and humidity at which tools are sometimes tested, but either term can be used for most purposes.
For air compressors, CFM is displayed along with pressure (PSI) because the volume of air being delivered depends on the pressure it is being released at. Increasing the air pressure usually means that less air will be delivered, or less CFM