HTML
Last updated
Was this helpful?
Last updated
Was this helpful?
A mark-up language is different than a programming language. It doesn't have any programming logic or code that is executed to perform some action. It just allows you to annotate the text in the document to provide extra meaning to the content. The browser uses the annotations to know how to display the page.
In computer text processing, a markup language is a system for annotating a document in a way that is visually distinguishable from the content. It is used only to format the text, so that when the document is processed for display, the markup language does not appear. The idea and terminology evolved from the "marking up" of paper manuscripts (i.e., the revision instructions by editors), which is traditionally written with a red pen or blue pencil on authors' manuscripts. - Wikipedia
HTML consists of markup elements (opening and closing tags) that wrap content to mark it for specific formatting.
Markup elements can contain attributes (name/value pairs) on the opening tag to specify additional information.
A tag is the HTML element name enclosed in angle brackets
<a> is the opening tag
</a> is the closing tag
An attribute comes after the HTML element name within the angle brackets
href="https://jellyfish.html" is the attribute
href is the attribute name
http://jellyfish.html is the attribute value
The content is the part of the code in between the opening and closing tags
Jelly Fish Facts is the content
Test for Understanding: Identify opening and closing tags, attribute name/values and content in the following HTML.
There are lots of different markup elements: too many to list here. The text-formatting, image and hyper-links (anchors) elements, many of which were used in the example above, are what you will use most frequently. Other common elements support including videos, forms and tables in your page.
Some elements do not contain any content between the opening and closing tags. In this case, the element is called a self-closing tag and can be simplified by having just a single tag with the "/" symbol at the end.
The image element is an example of a self-closing tag and can be written as follows.
For a full list of self-closing elements, see the MDN Documentation.
Anything that starts with <!-- and ends with --> will be ignored by the browser. This is useful for documenting your code and making notes to yourself, or for commenting out HTML that you are debugging.
You can add as much white-space as you want within the text of an element, and it will be ignored.
While there are ways to enforce HTML code to follow the rules, browsers have always attempted to gracefully handle syntax errors in HTML. The HTML that currently exists on the web is full of such errors, so it is not possible to change this behavior now without breaking lots of websites.
It's up to you to carefully review your HTML code to make sure the syntax is correct, otherwise you'll get unexpected results as the web browser attempts to correct errors.
