Section 4.9. Special Character Encoding

4.9. Special Character Encoding

For the most part, characters within documents that are not part of a tag are rendered as is by the browser. However, some characters have special meaning and are not directly rendered, and other characters can't be typed into the source document from a conventional keyboard. Special characters need either a special name or a numeric character encoding for inclusion in a document.

4.9.1. Special Characters

As has become obvious in the discussion and examples leading up to this section, three characters in source documents have very special meaning: the less-than sign ( < ), the greater-than sign ( > ), and the ampersand ( & ). These characters delimit tags and special character references. They'll confuse a browser if left dangling alone or with improper tag syntax, so you have to go out of your way to include their actual, literal characters in your documents. ^[*]

^[*] The only exception is that these characters may appear literally within the <listing> and <xmp> tags, but this is a moot point because the tags are obsolete.

Similarly, you have to use special encoding to include double quotation mark characters within a quoted string, or when you want to include a special character that doesn't appear on your keyboard but is part of the ISO Latin-1 character set that most browsers implement and support.

4.9.2. Inserting Special Characters

To include a special character in your document, enclose either its standard entity name or a pound sign ( # ) and its numeric position in the Latin-1 standard character set ^[*] inside a leading ampersand and an ending semicolon, without any spaces in between. Whew. That's a long explanation for what is really a simple thing to do, as the following examples illustrate . The first example shows how to include a greater-than sign in a snippet of code by using the character's entity name. The second demonstrates how to include a greater-than sign in your text by referencing its Latin-1 numeric value:

^[*] The popular ASCII character set is a subset of the more comprehensive Latin-1 character set. Composed by the well-respected International Organization for Standardization (ISO), the Latin-1 set is a list of all letters , numbers , punctuation marks, and so on, commonly used by Western-language writers, organized by number and encoded with special names . Appendix F contains the complete Latin-1 character set and encoding.

 if a > b, then t = 0 if a > b, then t = 0 

Both examples cause the text to be rendered as follows :

 if a > b, then t = 0 

The complete set of character entity values and names appears in Appendix F. You could write an entire document using character encodings, but that would be silly.