First developed by Tim Berners-Lee in 1990, HTML is short for HyperText Markup Language. HTML is used to create electronic documents (called pages) that are displayed on the World Wide Web. Each page contains a series of connections to other pages called hyperlinks. Every web page you see on the Internet is written using one version of HTML code or another.
HTML code ensures the proper formatting of text and images so that your
Internet browser may display them as they are intended to look. Without HTML, a browser would not know how to display text as
elements or load images or other elements. HTML also provides a basic structure of the page, upon which
Cascading Style Sheets are overlaid to change its appearance. One could think of HTML as the bones (structure) of a web page, and CSS as its skin (appearance).
What does an HTML tag look like?
As seen above in the above HTML tag example, there are not many components. Almost all HTML tags have an opening tag that contains the name with any
attributes and a close tag that contains a
forward slash and the name of the tag that is being closed. For tags that do not have a closing tag like the
<img> tag, it is best practice to end the tag with a forward slash.
Each tag is contained within a
less than and
greater than angle brackets and everything between the opening and closing tag is displayed or affected by the tag. In the above example, the
<a> tag is creating a link called "Computer Hope" that is pointing to the hope.html file.
What does HTML look like?
The following is an example of a basic
web page written in HTML as well as a description of each section and its function.
<!DOCType HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "https://www.w3.org/TR/html4/loose.dtd">
<html lang="en"><head>
<title>Example page</title>
<meta http-equiv="Content-Type" content="text/html; charset=windows-1252">
</head>
<body>
<h1>This is a heading</h1>
<p>This is an example of a basic HTML page.</p>
</body></html>
The box above contains the key ingredients to a basic web page. The first line (DOCType) describes what version of HTML the page was written in so that an Internet browser can interpret the text that follows. Next, the HTML opening
tag lets the browser know that it is reading HTML code. The HTML tag is followed by the
head section which contains information about the page such as its title,
meta tags, and where to locate the CSS file. The
body section is all content that is viewable on the browser. For example, all the text you see here is contained within the body tags. Finally, closing tags wrap each
elementfor proper
syntax.
What is HTML5?
HTML5 is the update made to HTML from HTML4 (
XHTML follows a different version numbering scheme). It uses the same basic rules as HTML4, but adds some new tags and attributes which allow for better semantics and for dynamic elements that are activated using
JavaScript. New elements include section,
<article>,
<aside>,
<audio>,
<bdi>,
<canvas>,
<datalist>,
<details>,
<embed>,
<figure>,
<figcaption>,
<footer>,
<header>,
<keygen>,
<mark>,
<meter>,
<nav>,
<output>,
<progress>,
<rp>,
<rt>,
<ruby>,
<time>,
<track>,
<video>, and
<wbr>. There are also new input types for
forms, which include tel, search, url, email, datetime, date, month, week, time, datetime-local, number, range, and color.
With the increasing movement to keep structure and style separate, a number of styling elements have been removed along with those that had accessibility issues or saw very little use. These following elements should no longer be used in HTML code:
<acronym>,
<applet>,
<basefont>,
<big>,
<center>,
<dir>,
<font>,
<frame>,
<frameset>,
<noframes>,
<strike>, and
<tt>. HTML5 also simplifies the
doctype declaration to the tag in the following box.
<!doctype html>
What does HTML5 look like?
As shown below the HTML5 code is very similar to the earlier HTML4 example, but is much cleaner with the revised doctype tag.
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>Example page</title>
</head>
<body>
<h1>This is a heading</h1>
<p>This is an example of a basic HTML page.</p>
</body>
</html>
How to create and view HTML
Because HTML is a markup language it can be created and viewed in any
text editor as long as it is saved with a .htm or .html
file extension. However, most find it easier to design and create web pages in HTML using an
HTML editor.
Which file extensions are used with HTML?
HTML files use either the .htm or .html
file extension. Older versions of Windows (Windows 3.x) only allow three-letter file extensions, so they used .htm instead of .html. However, both file extensions have the same meaning, and either may be used today. That being said, we recommend sticking to one naming convention as certain web servers may prefer one extension over the other.
Note: Web pages that are created using a
scripting language like
Perl,
PHP, or
Python have a different extension even though they only show HTML in the source code.