This command will show how many kilometers there are in a light year.
jason$ units -t '1 light year/kilometers' 9.4605284e+12
If I travelled 800m in 9.58 seconds how many miles per hour is this?
jason$ units -t '800m/9.58s' 'miles/hour' 186.80053
Using it this way, I can work out that 12 miles equals 19.3 kilometers.
jason$ units Currency exchange rates from www.timegenie.com on 2015-10-14 2919 units, 109 prefixes, 88 nonlinear units You have: 12 miles You want: kilometers * 19.312128 / 0.051780933
Changing 2 liters into gallons.
jason$ units Currency exchange rates from www.timegenie.com on 2015-10-14 2919 units, 109 prefixes, 88 nonlinear units You have: 2 liters You want: gallons * 0.5283441 / 1.8927059 You have: ^C
Converting 12 inches into centimeters.
jason$ units '12 inches' 'centimeters' * 30.48 / 0.032808399
How many yards in 1 kilometer?
jason$ units '1 kilometer' 'yards' * 1093.6133 / 0.0009144
The units command is very useful for find out what units of measurement equal in other units. A very useful Linux command indeed.