http://www.w3.org/TR/SVG/animate.html#RelationshipToSMILAnimation
SVG supports the following four animation elements which are defined in the SMIL Animation specification:
'animate'
allows scalar attributes and properties to be assigned different values over time
'set'
a convenient shorthand for 'animate', which is useful for assigning animation values to non-numeric attributes and properties, such as the 'visibility' property
'animateMotion'
moves an element along a motion path
'animateColor'
modifies the color value of particular attributes or properties over time
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Additionally, SVG includes the following compatible extensions to SMIL Animation:
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'animateTransform'
modifies one of SVG's transformation attributes over time, such as the transform attribute
path attribute
SVG allows any feature from SVG's path data syntax to be specified in a path attribute to the 'animateMotion' element (SMIL Animation only allows a subset of SVG's path data syntax within a path attribute)
'mpath' element
SVG allows an 'animateMotion' element to contain a child 'mpath' element which references an SVG 'path' element as the definition of the motion path
keyPoints attribute
SVG adds a keyPoints attribute to the 'animateMotion' to provide precise control of the velocity of motion path animations
rotate attribute
SVG adds a rotate attribute to the 'animateMotion' to control whether an object is automatically rotated so that its x-axis points in the same direction (or opposite direction) as the directional tangent vector of the motion path