HTML Attributes (HTML Tutorial part 4)

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Attributes are used to amplify tags. What we mean by amplify is that when a web browser interprets a tag, it will also search for set attributes and then display the element (tags+attributes) in its entirety. At some point you may want to give your body element a background color or perhaps change the width of a table. All of these things and more can be achieved using Attributes.

Many HTML tags have a unique set of their own attributes. These will be discussed as each tag is introduced throughout the tutorial. Right now we want to focus on a set of generic attributes that can be used with just about every HTML Tag in existence.
Attributes are placed within the opening tag and they follow a precise syntax (format).

HTML - Class or ID Attribute

The class and id attributes are nearly identical. They play no direct role in formatting your elements but rather serve behind the scenes for scripting and Cascading Style Sheets (CSS). The role of classification and identifying elements will become more apparent as your learn CSS.
The idea is that you can classify or id certain a tag and later format the tag using Cascading Style Sheets. It becomes necessary when you have two or more of the same element on a page (like a <p> tag) but want them to be different in appearance.

HTML Code:

<p id="italicsparagraph">Paragraph type 1 Italics</p>
<p id="boldparagraph">Paragraph type 2 Bold</p>

Classification Attributes:

Paragraph type 1 Italics
Paragraph type 2 Bold

HTML - Name Attribute

Name is much different than id and class. By allotting a name to an element, that name becomes a scripting variable for scripting languages such as Javascript, ASP, and PHP. The name attribute is seen most often with forms and other user-input elements.

HTML Code:

<input type="text" name="TextField" />

The Name Game:

This attribute has no effect on the display of the text field, but behind the scenes it plays a huge identification role.

HTML - Title Attribute

This is a neat little perhaps, forgotten attribute. This attribute titles an element and adds a tiny text pop-up to any HTML element. Much like the text pop-ups of word processing programs, these attributes should not be forgotten. You may title an element anything you would like, the effects of this attribute are not seen until you hover your mouse over the element for a few seconds.

HTML Code:

<h2 title="Hello There!">Titled Heading Tag</h2>

Title Attribute:

Titled Heading Tag

Hover your mouse over the display heading to see the magic of the title attribute! This provides your web site with some user interaction which is priceless. Do not overlook the title attribute.

HTML - Align Attribute

If you wish to change the horizontal location of your elements you may do so using the align attribute. You may align things left, right, or center. By default most elements are automatically aligned left unless otherwise specified.

HTML Code:

<h2 align="center">Centered Heading</h2>

Display:

Centered Heading

HTML Code:

<h2 align="left">Left aligned heading</h2>

<h2 align="center">Centered Heading</h2>

<h2 align="right">Right aligned heading</h2>

Display:

Left aligned heading

Centered heading

Right aligned heading

Attribute Defaults

Many tags are assigned default attributes. This means that unless a tag attribute is specified by you the creator, it will have some distinct attributes. For example, a paragraph tag will always align its text to the left unless it has an align attribute in it specifying otherwise. Also elements placed within a table are vertically centered and to the left unless otherwise specified. As you code and learn about each of the different HTML elements, you will become aware of many of these defaults.

Generic Attributes

Attributes exist to modify HTML tags allowing for complete customization of a website. Here's a table of some other attributes that are readily usable with many of HTML's tags.
AttributeOptionsFunction
alignright, left, centerHorizontally aligns tags
valigntop, middle, bottomVertically aligns tags within an HTML element.
bgcolornumeric, hexidecimal, RGB valuesPlaces a background color behind an element
backgroundURLPlaces an background image behind an element
idUser DefinedNames an element for use with Cascading Style Sheets.
classUser DefinedClassifies an element for use with Cascading Style Sheets.
widthNumeric ValueSpecifies the width of tables, images, or table cells.
heightNumeric ValueSpecifies the height of tables, images, or table cells.
titleUser Defined"Pop-up" title for your elements.