I was wondering that the textbox itself identifies its type and when clicked inside textbox it gives the suggestion for that. For a instance i am creating a textbox for mobile no and when click inside the textbox it correctly detects it. Can anyone explain me how it was coded. It was browser feature or HTML feature?
Here is the Image explanation

This features of modern browsers is called auto-fill option, where the browser recognizes that you have performed a specific search before and suggests information that you have typed before. For sweepers, auto-fill saves a ton of time. When Roboform doesn’t fill out a form for me, I usually only have to double-click in the text field and select the data I want from the drop-down list of options. This is particularly useful for daily sweepstakes that require codes.