1:2.8

Maximum aperture is f2.8

F3.5-6.3

 Maximun aperture is variable- 3.5 at the lower focal length

AF

Auto focusing

IF

Internal focusing

EF

EFs

Dx

IS

Image stabilization- canon and tamron lenses

VR

Vibration reduction-nikon lenses

L

Luxury- denoted by a red line, these are expensive higher quality lenses from canon

 xx mm- xx mm (eg 17mm-40mm)

 A zoom lens of focal length xx mm  to xx mm

 USM

 Ultra sonic motor (canon)

 SWM

 Silent wave motor (Nikon)

 APO