jQuery 1.4 Animation Techniques - Index of

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Chapter 2
We can control the duration of the animation using the duration argument to specify either
an integer in milliseconds or one of the strings slow or fast, which are shortcuts for
durations of 600 or 200 milliseconds, respectively.
We can also supply 0 as the duration argument, which will effectively disable the animation.
It's unlikely that we'd need to do this as it would be more efficient to not use an animation at
all, but it is useful to know. I should point out that the fade will still occur; it will just happen
over a duration of 0 milliseconds.
The duration argument relates to the length of time the animation takes to run,
not the speed of the animation. Therefore, a higher value will mean a slower,
longer animation and not a faster, shorter animation.
The easing argument can be changed from its default value of swing to linear, which
causes the animation to progress at the same speed throughout the animation. The default,
swing, causes the animation to start slowly, speed up slightly, and then slow down towards
the end of the animation.
The number of easing types can be greatly increased using plugins. We'll look
at the extra easing types added by jQuery UI later in the book.
We may supply a callback function (either a function reference or an anonymous function,
with the latter being more common-place). This callback function will be executed after the
animation ends for each element in the selection, so it may be triggered more than once if
more than a single element is being animated.
jQuery's Unified Animation API
In addition to the fading methods looked at in this chapter, it is worth noting at this stage
that any of the animation methods exposed by jQuery can accept the strings slow or fast
as the value of the duration argument, and they will always equate to durations of 600 or
200 milliseconds, respectively.
Any other strings that are supplied will be ignored and will cause the animation to take its
default duration of 400 milliseconds (as if no duration argument had been supplied). Any
integer, representing an actual length of time in milliseconds, can also be supplied.
Additionally, all jQuery animation methods can have easing configured, and all can accept a
callback function as an argument. Each of the animation methods work and are used in the
same way; it is just the effect which differs. This makes using the methods easy and intuitive.