map elementStatus: Last call for comments
nameinterface HTMLMapElement : HTMLElement {
           attribute DOMString name;
  readonly attribute HTMLCollection areas;
  readonly attribute HTMLCollection images;
};
   The map element, in conjunction with any
  area element descendants, defines an image
  map. The element represents its children.
The name attribute
  gives the map a name so that it can be referenced. The attribute
  must be present and must have a non-empty value with no space characters. The value of the
  name attribute must not be a
  compatibility-caseless
  match for the value of the name
  attribute of another map element in the same
  document. If the id attribute is also
  specified, both attributes must have the same value.
areasReturns an HTMLCollection of the area elements in the map.
imagesReturns an HTMLCollection of the img and object elements that use the map.
area elementStatus: Last call for comments
map element ancestor.altcoordsshapehreftargetrelmediahreflangtypeinterface HTMLAreaElement : HTMLElement {
           attribute DOMString alt;
           attribute DOMString coords;
           attribute DOMString shape;
  stringifier attribute DOMString href;
           attribute DOMString target;
           attribute DOMString rel;
  readonly attribute DOMTokenList relList;
           attribute DOMString media;
           attribute DOMString hreflang;
           attribute DOMString type;
  // URL decomposition IDL attributes
           attribute DOMString protocol;
           attribute DOMString host;
           attribute DOMString hostname;
           attribute DOMString port;
           attribute DOMString pathname;
           attribute DOMString search;
           attribute DOMString hash;
};
   The area element represents either a
  hyperlink with some text and a corresponding area on an image
  map, or a dead area on an image map.
If the area element has an href attribute, then the
  area element represents a hyperlink. In
  this case, the alt
  attribute must be present. It specifies the text of the
  hyperlink. Its value must be text that, when presented with the
  texts specified for the other hyperlinks of the image
  map, and with the alternative text of the image, but without
  the image itself, provides the user with the same kind of choice as
  the hyperlink would when used without its text but with its shape
  applied to the image. The alt
  attribute may be left blank if there is another area
  element in the same image map that points to the same
  resource and has a non-blank alt
  attribute.
If the area element has no href attribute, then the area
  represented by the element cannot be selected, and the alt attribute must be omitted.
In both cases, the shape and
  coords attributes specify the
  area.
The shape
  attribute is an enumerated attribute. The following
  table lists the keywords defined for this attribute. The states
  given in the first cell of the rows with keywords give the states to
  which those keywords map. 
| State | Keywords | 
|---|---|
| Circle state | circle
      | 
| Default state | default
      | 
| Polygon state | poly
      | 
| Rectangle state | rect
      | 
The attribute may be omitted. The missing value default is the rectangle state.
The coords
  attribute must, if specified, contain a valid list of
  integers. This attribute gives the coordinates for the shape
  described by the shape
  attribute. 
In the circle state,
  area elements must have a coords attribute present, with three
  integers, the last of which must be non-negative. The first integer
  must be the distance in CSS pixels from the left edge of the image
  to the center of the circle, the second integer must be the distance
  in CSS pixels from the top edge of the image to the center of the
  circle, and the third integer must be the radius of the circle,
  again in CSS pixels.
In the default state
  state, area elements must not have a coords attribute. (The area is the
  whole image.)
In the polygon state,
  area elements must have a coords attribute with at least six
  integers, and the number of integers must be even. Each pair of
  integers must represent a coordinate given as the distances from the
  left and the top of the image in CSS pixels respectively, and all
  the coordinates together must represent the points of the polygon,
  in order.
In the rectangle state,
  area elements must have a coords attribute with exactly four
  integers, the first of which must be less than the third, and the
  second of which must be less than the fourth. The four points must
  represent, respectively, the distance from the left edge of the
  image to the left side of the rectangle, the distance from the
  top edge to the top side, the distance from the left edge to the
  right side, and the distance from the top edge to the bottom side,
  all in CSS pixels.
The target,
  rel, media, hreflang, and type attributes must be omitted
  if the href attribute is
  not present.
Status: Last call for comments
An image map allows geometric areas on an image to be associated with hyperlinks.
An image, in the form of an img element or an
  object element representing an image, may be associated
  with an image map (in the form of a map element) by
  specifying a usemap attribute on
  the img or object element. The usemap attribute, if specified,
  must be a valid hash-name reference to a
  map element.
Consider an image that looks as follows:

If we wanted just the colored areas to be clickable, we could do it as follows:
<p>
 Please select a shape:
 <img src="shapes.png" usemap="#shapes"
      alt="Four shapes are available: a red hollow box, a green circle, a blue triangle, and a yellow four-pointed star.">
 <map name="shapes">
  <area shape=rect coords="50,50,100,100"> <!-- the hole in the red box -->
  <area shape=rect coords="25,25,125,125" href="red.html" alt="Red box.">
  <area shape=circle coords="200,75,50" href="green.html" alt="Green circle.">
  <area shape=poly coords="325,25,262,125,388,125" href="blue.html" alt="Blue triangle.">
  <area shape=poly coords="450,25,435,60,400,75,435,90,450,125,465,90,500,75,465,60"
        href="yellow.html" alt="Yellow star.">
 </map>
</p>
  Status: Last call for comments
The math element from the MathML
  namespace falls into the embedded content,
  phrasing content, and flow content
  categories for the purposes of the content models in this
  specification.
The semantics of MathML elements are defined by the MathML specification and other relevant specifications. [MATHML]
Here is an example of the use of MathML in an HTML document:
<!DOCTYPE html>
<html>
 <head>
  <title>The quadratic formula</title>
 </head>
 <body>
  <h1>The quadratic formula</h1>
  <p>
   <math>
    <mi>x</mi>
    <mo>=</mo>
    <mfrac>
     <mrow>
      <mo form="prefix">−</mo> <mi>b</mi>
      <mo>±</mo>
      <msqrt>
       <msup> <mi>b</mi> <mn>2</mn> </msup>
       <mo>−</mo>
       <mn>4</mn> <mo></mo> <mi>a</mi> <mo></mo> <mi>c</mi>
      </msqrt>
     </mrow>
     <mrow>
      <mn>2</mn> <mo></mo> <mi>a</mi>
     </mrow>
    </mfrac>
   </math>
  </p>
 </body>
</html>
  Status: Last call for comments
The svg element from the SVG
  namespace falls into the embedded content,
  phrasing content, and flow content
  categories for the purposes of the content models in this
  specification.
When the SVG foreignObject element contains elements
  from the HTML namespace, such elements must all be
  flow content. [SVG]
The content model for title elements in the
  SVG namespace inside HTML documents is
  phrasing content. (This further constrains the
  requirements given in the SVG specification.)
The semantics of SVG elements are defined by the SVG specification and other relevant specifications. [SVG]
The SVG specification includes requirements regarding the
  handling of elements in the DOM that are not in the SVG namespace,
  that are in SVG fragments, and that are not included in a
  foreignObject element. This specification does
  not define any processing for elements in SVG fragments that are not
  in the HTML namespace; they are considered neither conforming nor
  non-conforming from the perspective of this specification.
Status: Last call for comments
  The width and height attributes on
  img, iframe, embed,
  object, video, and, when their type attribute is in the Image Button state,
  input elements may be specified to give the dimensions
  of the visual content of the element (the width and height
  respectively, relative to the nominal direction of the output
  medium), in CSS pixels. The attributes, if specified, must have
  values that are valid
  non-negative integers.
The specified dimensions given may differ from the dimensions specified in the resource itself, since the resource may have a resolution that differs from the CSS pixel resolution. (On screens, CSS pixels have a resolution of 96ppi, but in general the CSS pixel resolution depends on the reading distance.) If both attributes are specified, then one of the following statements must be true:
The target ratio is the ratio of the
  intrinsic width to the intrinsic height in the resource. The specified width and specified
  height are the values of the width and height attributes respectively.
The two attributes must be omitted if the resource in question does not have both an intrinsic width and an intrinsic height.
If the two attributes are both zero, it indicates that the element is not intended for the user (e.g. it might be a part of a service to count page views).
The dimension attributes are not intended to be used to stretch the image.