Elements can also have attributes which don’t appear in the end user content, such as
<p class="editor quote">This is the best thing I've ever read</p> in which case the attribute is
class="editor quote". In this example
class is the attribute name and
"editor quote" is the attribute value. - The
class attribute allows you to give the element an identifier that can be used to target the content of the element. (With CSS for example). Attributes should always have the following: - A space between it and the element name (or the previous attribute, if the element already has one or more attributes). - The attribute name followed by an equal sign. - The attribute value wrapped by opening and closing quotation marks.
Note: Simple attribute values that don’t contain ASCII whitespace (or any of the characters
" ' = < > )can remain unquoted, but it is recommended that you quote all attribute values, as it makes the code more consistent and understandable.
- CSS Basics