The dy attribute indicates a shift along the y-axis on the position of an element or its content.

The pathLength attribute lets authors specify a total length for the path, in user units. This value is then used to calibrate the browser's distance calculations with those of the author, by scaling all distance computations using the ratio pathLength / (computed value of path length).

The keyTimes attribute represents a list of time values used to control the pacing of the animation.

The xChannelSelector attribute indicates which color channel from in2 to use to displace the pixels in in along the x-axis.

The y2 attribute is used to specify the second y-coordinate for drawing an SVG element that requires more than one coordinate. Elements that only need one coordinate use the y attribute instead.

The InternalError object indicates an error that occurred internally in the JavaScript engine.

The delete operator removes a property from an object. If the property's value is an object and there are no more references to the object, the object held by that property is eventually released automatically.

The <mpath> sub-element for the <animateMotion> element provides the ability to reference an external <path> element as the definition of a motion path.

The <switch> SVG element evaluates any requiredFeatures, requiredExtensions and systemLanguage attributes on its direct child elements in order, and then renders the first child where these attributes evaluate to true.

The addition assignment operator (+=) adds the value of the right operand to a variable and assigns the result to the variable. The types of the two operands determine the behavior of the addition assignment operator. Addition or concatenation is possible.