Horizontal Rules

The <HR> element is used for horizontal rules that act as dividers between sections. The SRC attribute can be used to designate a custom graphic, otherwise subclass HR with the CLASS attribute and specify the appropriate rendering with an associated style sheet.

Permitted Attributes

ID

An SGML identifier used as the target for hypertext links or for naming particular elements in associated style sheets. Identifiers are NAME tokens and must be unique within the scope of the current document.

CLASS

This a space separated list of SGML NAME tokens and is used to subclass tag names. For instance, <H2 CLASS=Section> defines a level 2 header that acts as a section header. By convention, the class names are interpreted hierarchically, with the most general class on the left and the most specific on the right, where classes are separated by a period. The CLASS attribute is most commonly used to attach a different style to some element, but it is recommended that where practical class names should be picked on the basis of the element's semantics, as this will permit other uses, such as restricting search through documents by matching on element class names. The conventions for choosing class names are outside the scope of this specification.

CLEAR

This attribute is common to all block-like elements. When text flows around a figure or table in the margin, you sometimes want to position the rule below the figure rather than alongside it. The CLEAR attribute allows you to move down unconditionally:

clear=left

move down until left margin is clear

clear=right

move down until right margin is clear

clear=all

move down until both margins are clear

Alternatively, you can decide to place the rule alongside the figure just so long as there is enough room. The minimum width needed is specified as:

clear="40 en"

move down until there is at least 40 en units free

clear="100 pixels"

move down until there is at least 100 pixels free

The style sheet (or browser defaults) may provide default minimum widths for each class of block-like elements.

SRC

Specifies a custom image for the rule. The image is specified as a URI. This attribute may appear together with the MD attribute.

MD

Specifies a message digest or cryptographic checksum for the associated graphic specified by the SRC attribute. It is used when you want to be sure that a linked object is indeed the same one that the author intended, and hasn't been modified in any way. For instance, MD="md5:jV2OfH+nnXHU8bnkPAad/mSQlTDZ", which specifies an MD5 checksum encoded as a base64 character string. The MD attribute is generally allowed for all elements which support URI based links.