HTML Tags

As told earlier, HTML is a markup language and makes use of various tags to format the content. These tags are enclosed within angle braces <Tag Name>. Except few tags, most of the tags have their corresponding closing tags. For example, <html> has its closing tag </html> and <body> tag has its closing tag </body> tag etc.

Above example of HTML document uses the following tags −

<b>Serial Number</b>	<b>Tag</b>	<b> Description</b>
1	<b><!DOCTYPE...></b>	This tag defines the document type and HTML version.
2	<html>	This tag encloses the complete HTML document and mainly comprises of document header which is represented by <head>...</head> and document body which is represented by <body>...</body> tags.
3	<head>	This tag represents the document's header which can keep other HTML tags like <title>, <link> etc.
4	<title>	The <title> tag is used inside the <head> tag to mention the document title.
5	<body>	This tag represents the document's body which keeps other HTML tags like <h1>, <div>, <p> etc.
6	<h1>	This tag represents the heading.
7	<p>	This tag represents a paragraph.

HTML Document Structure

A typical HTML document will have the following structure −

<html>
   
   <head>
      Document header related tags
   </head>
   
   <body>
      Document body related tags
   </body>
   
</html>

We will study all the header and body tags in subsequent chapters, but for now let's see what is document declaration tag.

Heading Tags

Any document starts with a heading. You can use different sizes for your headings. HTML also has six levels of headings, which use the elements <h1>, <h2>, <h3>, <h4>, <h5>, and <h6>. While displaying any heading, browser adds one line before and one line after that heading.

Paragraph Tag

The <p> tag offers a way to structure your text into different paragraphs. Each paragraph of text should go in between an opening <p> and a closing </p>.

Line Break Tag

Whenever you use the <br /> element, anything following it starts from the next line. This tag is an example of an empty element, where you do not need opening and closing tags, as there is nothing to go in between them.

The <br /> tag has a space between the characters br and the forward slash. If you omit this space, older browsers will have trouble rendering the line break, while if you miss the forward slash character and just use <br> it is not valid in XHTML.

Centering Content

You can use <center> tag to put any content in the center of the page or any table cell.

Horizontal Lines

Horizontal lines are used to visually break-up sections of a document. The <hr> tag creates a line from the current position in the document to the right margin and breaks the line accordingly.

Again <hr /> tag is an example of the empty element, where you do not need opening and closing tags, as there is nothing to go in between them.

The <hr /> element has a space between the characters hr and the forward slash. If you omit this space, older browsers will have trouble rendering the horizontal line, while if you miss the forward slash character and just use <hr> it is not valid in XHTML.

Preserve Formatting

Sometimes, you want your text to follow the exact format of how it is written in the HTML document. In these cases, you can use the preformatted tag <pre>.

Any text between the opening <pre> tag and the closing </pre> tag will preserve the formatting of the source document.