Remarks
The form tag includes important attributes method and action.
The method attribute defines the kind of HTTP request sent when the form is submitted: its value can be get or post (see later).
The action attribute is a URL. In normal use it will locate an executable program on the server. In this case it is a reference to my “dummy server”.
An input tag with type attribute text represents a text input field.
An input tag with type attribute submit represents a “submit” button.