A HTML editor is an application software for creating webpages. Although the HTML code of a web page can be written with any text editor, HTML editing software often offers convenience and functionality. For example, many HTML editors can handle not only HTML, but also related technologies such as CSS and templates.

Types

There are two flavors of HTML editors: text and What You See Is What You Get (WYSIWYG).

Text editors

Text editors usually provide syntax highlighting, toolbars and keyboard shortcuts for quickly inserting HTML elements. Wizards and dialogue boxes help with tasks like adding the basic page structure or creating tables.

Text editors require at least a basic understanding of HTML and CSS.

WYSIWYG editors

So-called WYSIWYG editors provide an editing interface which resembles how the page will be displayed in a web browser. Often the WYSIWIG editor will also have a mode to edit HTML directly like a text HTML editor. Because using a WYSIWYG editor does not require any HTML knowledge they are easier for an average computer user.

One way to achieve this is to embed the layout engine used by the web browser. In this way, the rendering result should be identical to that produced by the web browser.

WYSIWIG editors are sometimes criticized because:

• They generally do not generate the most efficient HTML code.
• Users may be disappointed that the same page is rendered differently in different browsers

Valid HTML code

HTML is a structured markup language. There are certain rules on how HTML must be written if it is to conform to W3C standards. Following these rules allows for sites that are accessible to handicapped people, and also to wireless devices like mobile phones or PDAs.

WYSIWYG editors sometimes fail to adhere to these rules, turning out code that works to some degree but is syntactically incorrect. Older versions of Microsoft FrontPage, in particular, were notorious for producing code that would only work properly in Internet Explorer, as (to a lesser degree) was Netscape Composer of Netscape Navigator. Then again, text editors do not provide complete validation for all of these rules either, so valid code still relies on the knowledge and expertise of the coder.

Recent versions of popular HTML editors generally produce more acceptable code.

Difficulties in achieving WYSIWYG

A given webpage may not display the same on all browsers, for several reasons:

• HTML only defines the structure of the document and does not give precise design control.
• Different browsers may render the same markup differently. The same page will display differently in Internet Explorer and Mozilla and very differently again in the (text-only) Lynx browser, on a PDA or mobile phone, or in a speech or braille browser.
• Browsers have a range of user settings - font size and colour can be adjusted at the user's discretion, and many modern browsers allow even more user control over page appearance. All an author can do is suggest an appearance.
• Web browsers, like all computer software, have bugs and may not conform to standards.

What you see may be what most visitors get, but it is not guaranteed to be what everyone gets.

See also

• List of HTML editors
• Comparison of HTML editors