The xlink:arcrole attribute specifies a contextual role for the element and corresponds to the RDF Primer notion of a property.

As an XML dialect, SVG is namespaced. It is important to understand the concept of namespaces and how they are used if you plan to author SVG content. Namespaces are essential to user agents that support multiple XML dialects; browsers must be very strict. Taking the time to understand namespaces now will save you from future headaches.

The stroke-opacity attribute is a presentation attribute defining the opacity of the paint server (color, gradient, pattern, etc.) applied to the stroke of a shape.

The JavaScript strict mode-only exception "setting getter-only property" occurs when there is an attempt to set a new value to a property for which only a getter is specified.

The JavaScript exception "called on incompatible target (or object)" occurs when a function (on a given object), is called with a this not corresponding to the type expected by the function.

The tabindex attribute allows you to control whether an element is focusable and to define the relative order of the element for the purposes of sequential focus navigation.

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.

SVG images can be used as an image format, in a number of contexts. Browsers support SVG images in:

The writing-mode attribute specifies whether the initial inline-progression-direction for a <text> element shall be left-to-right, right-to-left, or top-to-bottom. The writing-mode attribute applies only to <text> elements; the attribute is ignored for <tspan>, <tref>, and <textPath> sub-elements. (Note that the inline-progression-direction can change within a <text> element due to the Unicode bidirectional algorithm and properties direction and unicode-bidi.)

The x attribute defines an x-axis coordinate in the user coordinate system.