Can anyone please explain the usage of the value attribute in the input tag.
This depends on the type of input. But generally - if the form is submitted to a server, it’s what the server receives in the POST object for that input.
For type=“text”, it’s the text that’s in the input field.
Similar for checkboxes and radio buttons.
For type=“button”, “reset” or “submit”, it’s the text that’s written on the button.