Characters which are not part of the normal printable [w:ASCII] character set, unicode characters, and some normal symbolic characters that have specific use in text markup require the use of an escape-code sequence to be entered as text into a text area or other input field on the website.

Common use cases include:

- Documentation describing how to write markup code
- Use of special characters such as the circle-c copyright symbol, ©
- Use of the ampersand character, &, which is normally reserved for the escape sequence.
- Math equations or code which may need the use of the comparison operator less-than, brackets, and so on.

These characters are rendered using the HTML entity escape sequence. A basic template follows:

&something;

Above, "something" will be replaced with a short abbreviation or symbolic/numeric sequence that identifies the requested character. A comprehensive list of character entities is provided [w:List_of_XML_and_HTML_character_entity_references|here].

The following is a list of the essential characters that have special meanings and therefore *must* be entered as an HTML entity.

- Open angle-bracket, or "less than" symbol: <
- As an entity: &lt;
- Open square-bracket, [
- As an entity: &#91;
- Ampersand, &
- As an entity: &amp;

Note that some exceptions may apply. For example "code" blocks in the Simple Text input format do not require use of escape codes. It is recommended that the document be checked for proper display in View mode after editing.