What does the 'mailto:' part of a hyperlink do?

The 'mailto:' part of a hyperlink specifically instructs the web browser to open the user's default email client, allowing them to send an email directly. When a user clicks on a hyperlink that begins with 'mailto:', it prompts the email application installed on their device to launch, pre-filling the recipient's email address provided in the link. This feature enhances usability by streamlining the process of composing an email without requiring users to manually enter the address, making it a convenient option for websites that encourage direct communication through email.

The other choices involve functionalities that are unrelated to the 'mailto:' protocol: linking to a webpage pertains to standard URL behavior, directing to a file usually involves a different file path rather than an email address, and providing a phone link typically uses formats like 'tel:' to initiate phone calls rather than sending emails.