HTML5 and semantic markup
HTML (HyperText Markup Language) is the code that is used to structure a web page and its content. For example, content could be structured within a set of paragraphs, a list of bulleted points, or using images and data tables.
HTML consists of a series of elements, which you use to enclose, or wrap, different parts of the content to make it appear a certain way, or act a certain way.
HTML Elements and Attributes
Elements can also have attributes that look like the following:
Attributes contain extra information about the element that you don't want to appear in the actual content. Attributes usually come in name/value pairs like: name="value"
Void elements
Some elements have no content and are called void elements. Take the element that we already have in our HTML page:
html <img src="images/firefox-icon.png" alt="My test image" />
This contains two attributes, but there is no closing tag and no inner content. This is because an image element doesn't wrap content to affect it. Its purpose is to embed an image in the HTML page in the place it appears.