Quote Originally Posted by BottomScratcher View Post
Low gears do have the highest ratios though. A first gear might be close to 3:1, and in a 6 speed box 5th gear might be just over 1:1, and 6th will be an overdrive ratio of about 0.6:1. Don't even start me on diff ratios.
In mathematical terms yes you are correct but in common usage it's one of those things like camera apertures that is referred to the opposite way to it's mathematical orientation.
On a camera an aperture of f2.8 is as being a large aperture whereas f11 is a much smaller aperture.
On a vehicle a 3:1 gear ratio is referred to as a lower ratio than 1:1 hence first gear is "low" gear and sixth is "high" gear. Referring to gears as low and high makes sense to those of us who learnt to drive in vehicles with three speed gearboxes.