A hyperlink is a bit of text, an image, or a button in a hypertext document that you can click. A hyperlink may include a link to another document or to another part of the current page. Hyperlinks are found on virtually every webpage to help navigate readers to other pages and websites.
Other types of files may also include hyperlinks. PDF files and Word documents often include hyperlinks to other parts of the document or an outside website. Presentation files may use hyperlinks to help a presenter to jump to a specific slide. eBooks include hyperlinks for readers to quickly jump to the start of a chapter from the table of contents, view an endnote by tapping its reference, or open another book by tapping a link.
The default formatting for a hyperlink on a webpage or in a document is blue, underlined text. However, web designers often customize the appearance of links to match the overall theme of a webpage or document, so you cannot always expect a hyperlink to keep its default look. Hyperlinks that use images instead of text do not receive any special formatting.
In HTML, a hyperlink uses the <a> tag. The tag includes the URL of the link's destination, as well as other optional attributes — whether the link is a file for download, how to include referrer information, or if the link should open in the same window or a new one. The tag surrounds the anchor text, which is the text that actually appears on the page and can be clicked. For example, here is the HTML code for a hyperlink to this website.