These three sliders correspond to the three methods described in the text: (1) just assume an update every 1/60th of a second, (2) measure the time between steps, and (3) use a global clock.

(1) This slider will either be a bit faster than 1 second end to end, or a bit slower than 2 seconds end to end (depending on your computer and browser).

(2) This slider should take approximately 1 second, but will be off because of rounding errors.

(3) This slider should really take 1 second to go end to end...

(4) This slider is the same as #1, except that we change the slider resolution to avoid rounding errors. It should take either 1 or 2 seconds end to end, depending on the computer.

(5) This is the same as #2, except that we avoid rounding errors by changing slider resolution. It should take 1 second.

(6) This is a version of strategy 2, except that rather than relying on storing the value in a slider, we store it ourselves, so we don't have to deal with rounding. This is a more realistic scenario.