HTML Forms - The Input Element

The most important form element is the input element. The input element is used to select user information. An input element can vary in many ways, depending on the type attribute. An input element can be of type text field, checkbox, password, radio button, submit button, and more.
The most common input types are described below: Text Fields input type=text defines a one-line input field that a user can enter text into:
First name:
Last name:

Password Field input type="password defines a password field:
Password:

Radio Buttons input type=radio defines a radio button. Radio buttons let a user select ONLY ONE of a limited number of choices:
Male
Female

Checkboxes input type=checkbox defines a checkbox. Checkboxes let a user select ZERO or MORE options of a limited number of choices.
I have a bike
I have a car

Submit Button input type=submit defines a submit button. A submit button is used to send form data to a server. The data is sent to the page specified in the form's action attribute. The file defined in the action attribute usually does something with the received input:
Username: