
Explanation/Reference:
Box 1-3: The <input type="range"> is used for input fields that should contain a value within a range.
Example
<input type="range" name="points" min="0" max="10">
Box 4:
The step attribute specifies the legal number intervals for an <input> element.
Example: if step="3", legal numbers could be -3, 0, 3, 6, etc.
Syntax
<input step="number">
number
Specifies the legal number intervals for the input field. Default is 1
Box 5: Use the value attribute to set the default value. Here: 37
Box 6: Definition and Usage
The required attribute is a boolean attribute.
When present, it specifies that an input field must be filled out before submitting the form.
Example
Username: <input type="text" name="usrname" required>
Reference: HTML Input Types
http://www.w3schools.com/html/html_form_input_types.asp