11 January, 2011

Written by on CSS Wizardry.

This article is only a small one, and to the vast majority it won’t be of much use, but I’m still astounded that today, in 2011, professional web designers and developers are still making this fundamental mistake. The difference between HTML elements, tags and attributes.

Elements

An element is a single ‘chunk’ of code comprising of an opening and closing tag.

<code><div>This is a div element</div></code>

This is a div element. Not a div tag.

Some elements have only one, self-closing tag:

Tags are the bits that make up elements. <div> is a tag. An opening and closing tag makes an element:

And:

Attributes

An attribute is a piece of code attached to a tag which supplies additional information:

<code><div <mark>class="some-class"</mark>>This is a div element</div></code>

This is an attribute.

So, when people say ‘I’ve used alt tags’, they haven’t; they’ve used alt attributes.

When people say ‘Don’t use tables, use div tags.’ they mean use div elements.

When people say ‘mark important text up in a strong tag’ they mean mark important text up in a strong element (made up of two strong tags).

<code>|<--             --element--            -->|
<tag attribute="value">Element content</tag></code>

This is probably really very basic for the majority of you, so apologies, but it really winds me up when I see developers making this mistake. Still.