Class 2 | Elements and Attributes | Learn HTML
HTML Elements
HTML elements are written with a start tag, with an end tag, with the content in between:
<tagname>content</tagname>The HTML element is everything from the start tag to the end tag:
<p>Dummy Text</p>Nested HTML Elements
HTML elements can be nested (elements can contain elements). All HTML documents consist of nested HTML elements. Below example contains four (4) HTML elements:
The <html> element defines the whole document. It has a start tag <html> and an end tag </html>. The element content is another HTML element (the <body> element).
<!DOCTYPE html>
<html>
<body>
<h1>My Heading</h1>
<p>My paragraph.</p>
</body>
</html>
The <body> element defines the document body. It has a start tag <body> and an end tag </body>. The element content is two other HTML elements (<h1> and <p>).
<body>
<h1>Dummy Text</h1>
<p>Lorem ipsum dolor</p>
</body>
The <h1> element defines a heading. It has a start tag <h1> and an end tag </h1>. The element content is: My Heading.
<h1>My Heading</h1>The <p> element defines a paragraph. It has a start tag <p> and an end tag </p>. The element content is: My paragraph.
<p>My paragraph.</p>Don’t Forget the End Tag
Some HTML elements will display correctly, even if you forget the end tag. Like <p> <small> <i> etc.
<html>
<body>
<p>My paragraph
</body>
</html>
Empty HTML Elements
HTML elements with no content are called empty elements. <br> is an empty element without a closing tag (the <br> tag defines a line break). Empty elements can be “closed” in the opening tag like this: <br />.
HTML5 does not require empty elements to be closed. But if you want stricter validation, or you need to make your document readable by XML parsers, you should close all HTML elements.
Use Lowercase Tags
HTML tags are not case sensitive: <P> means the same as <p>. The HTML5 standard does not require lowercase tags, but W3C recommends lowercase in HTML4, and demands lowercase for stricter document types.
HTML Attributes
- HTML elements can have attributes
- Attributes provide additional information about an element
- Attributes are always specified in the start tag
- Attributes come in name/value pairs like: name=”value”
The lang Attribute
The document language can be declared in the <html> tag. The language is declared in the lang attribute. Declaring a language is important for accessibility applications (screen readers) and search engines:
<!DOCTYPE html>
<html lang="en-US">
<body>
<h1>My Heading</h1>
<p>My paragraph.</p>
</body>
</html>
The title Attribute
HTML paragraphs are defined with the <p> tag. In this example, the <p> element has a title attribute. The value of the attribute is “paragraph”:
<p title="paragraph">W3Schools is a web developer's site. It provides tutorials and references covering
many aspects of web programming,including HTML, CSS, JavaScript, XML, SQL, PHP
etc. </p>
The href Attribute
HTML links are defined with the <a> tag. The link address is specified in the href attribute: Example
<a href="http://www.google.com">Google</a>Size Attributes
HTML images are defined with the <img> tag. The filename of the source (src), and the size of the image (width and height) are all provided as attributes: Example
<img src=“google.jpg" width="104" height="142">The alt Attribute
The alt attribute specifies an alternative text to be used, when an HTML element cannot be displayed. The value of the attribute can be read by “screen readers”. This way, someone “listening” to the webpage, i.e. a blind person, can “hear” the element.
<img src=“yahoo.jpg“ alt=“google” width="104“ height="142">Always Use Lowercase Attributes
The HTML5 standard does not require lower case attribute names.
W3C recommends lowercase in HTML4, and demands lowercase for stricter document types like XHTML.
Always Quote Attribute Values
The HTML5 standard does not require quotes around attribute values. The href attribute, demonstrated above, can be written as: <a href=http://www.google.com>
Single or Double Quotes?
Double style quotes are the most common in HTML, but single style can also be used. In some
situations, when the attribute value itself contains double quotes, it is necessary to use single
quotes: <p title=‘Smith “ShotGun” Jack’>