• Specifying different versions of HTML
  • Identifying and grouping elements
  • Comments, meta information and iframes

At this point, we have covered the main tags that fit nicely into groups and sections.

In this chapter, we will focus on some helpful topics that are not easily grouped together. You will learn about:

  • The different versions of HTML and how to indicate which version you are using
  • How to add comments to your code
  • Global attributes, which are attributes that can be used on any element, including the class and id attributes
  • Elements that are used to group together parts of the page where no other element is suitable
  • How to embed a page within a page using iframes
  • How to add information about the web page using the <meta> element
  • Adding characters such as angled brackets and copyright symbols



Since the web was first created, there have been several different versions of HTML.

Each new version was designed to be an improvement on the last (with new elements and attributes added and older code removed).

There have also been several versions of each browser used to view web pages, each of which implements new code. Not all web users, however, have the latest browsers installed on their computers, which means that not everyone will be able to view all of the latest features and markup.

Where you should be particularly aware of browsers not ...

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