You may use <select> (with nested option>) elements to build a drop-down menu of items from which a user can pick: By including the chosen attribute in an <option> element, that option will be shown by default. 

Additionally, if you want to group options into different categories, you can nest <option> elements in an <optgroup> element:

Definition and Application

• A drop-down list is created with the <select> HTML tag.
• The <select> element is most often used to gather user input in a form.

After the form is submitted, the name property is required to refer to the form data (if you omit the name attribute, no data from the drop-down list will be submitted).

• The id element is required to link the drop-down list to a label.

The choices in the drop-down list are defined by the <option> tags in the <select> element.