Element Attributes
What are Element Attributes in HTML?
An HTML element can have attributes. HTML element's attributes are appended to its opening tag or its sole tag.
ID & Class
Two of the most commonly used attributes are id
and class
.
Both id
and class
can be used for:
-
selecting the element for styling in CSS (
#
forid
,.
forclass
), -
selecting the element in JavaScript (
getElementById
forid
,getElementsByClassName().
forclass
)
Further, id
can be used for fragment identifier linking i.e. linking to a specific place in a document.
The difference between id
and class
is that:
-
in a given HTML document there can be only one element with a given
id
whereas there might be an unlimited number of elements with a givenclass
, -
a given HTML element can only have one
id
however an unlimited number of classes
<body>
<div id="horses" class="names, coloration">
...
</div>
<div id="witchers" class="names, schools">
...
<div>
</body>
Style
An HTML attribute can be styled in two ways:
-
through selecting in CSS and applying respective styling,
-
through applying inline styling using the
style
attribute.
<p style="background:black;color:white;">
White text on black background.
</p>
Nowadays, using inline styling is discouraged in favor of CSS.
Global Attributes
id
, class
and style
are examples of global attributes i.e. attributes common to many HTML elements.
Other notable HTML global attributes are:
-
autofocus
- indicates the element to be focused once the page loads, -
hidden
- prevents the element from rendering, -
lang
- indicates the element's content language, -
tabindex
- indicates the sequential position inTab
key navigation, -
title
- a description of the element which might be presented as a tooltip by a user agent, and -
event handlers such as
onblur
,onchange
,onclick
,onfocus
,onkeydown
,onkeypress
,onkeyup
,onmousedown
,onmouseenter
,onmouseleave
,onselect
,onsubmit
.