HTML, or Hypertext Markup Language, is a standardised markup language used for describing the content and hierarchical structure of pages that are displayed in a web browser. It uses a number of ‘elements’ that indicate how content is to be displayed in the browser, such as a title, heading, paragraph or hyperlink.

These HTML elements are formatted as HTML ‘tags’ which consist of a start and an end tag. Tags specify which element is being used and where the content it is describing begins and ends. These tags are invisible to the user but are viewable by the web browser for the purpose of interpreting how to display the web page.

Additionally, an element inside a start tag can also take a number of attributes which consist of name and value pairs. These provide additional information about the element’s behaviour and can also extend the functionality of HTML to incorporate the use of other languages, libraries, tools, and frameworks in the web page.


Using HTML tags correctly is important for SEO as they can impact how search engines navigate and make sense of a web page. Although not as heavily relied upon by search engines as they once were, HTML tags are still an important factor in SEO. There are a great many HTML tags and elements that can be used when creating a web page, each with its own value for SEO.

An example of this is anchor text tags which are considered important for SEO as they provide search engines with additional contextual information about the content and purpose of a linked web page. Further examples are the title and meta description tags which provide information that is crawled by search bots and is displayed in the search results.

Many CMS’s and add-ons create additional code within the HTML, which can lead to ‘code-bloat’ and slow websites down and even negatively affect SEO. HTML should generally be as clean as possible so that it is not difficult for search engines to crawl and understand the web pages in question.