From Aviation Wiki
- Indicated Airspeed (IAS) - the airspeed read directly from the airspeed indicator on an aircraft, driven by the pitot-static system. IAS is directly related to calibrated airspeed (CAS), but includes instrument errors and position error. Ref: 
- True Airspeed (TAS) - the speed of an aircraft relative to the airmass in which it flies. Ref: 
- Calibrated Airspeed (CAS) - the speed shown by a conventional airspeed indicator (IAS) after correction for instrument error and position error. Ref: 
- VA - Bottom of the yellow arc - Design maneuvering speed, also known as the "Speed for maximum control deflection."
- VFE - Top of the white arc - Speed for Maximum flap extended speed.