HTML Selector
Class Selector used to define a set of common functions or formats. HTML Elements
ID Selector used to define a specific HTML element, JavaScript and the CSS can be based on this ID value to manipulate and locate this particular HTML tags.
< style >
<!--
#yellowone
{
color:Yellow
}
-
</ style >
If a single element needs to be formatted when the page is output only on a certain medium, you should use the ID selector instead of the style that directly sets the HTML element. the inline style sheet for the property.
When you use an embedded and linked style sheet in a Web page, the display of an element needs to be re-set for a defined correlation style in the style sheet, using an inline style sheet to directly set the style property of the HTML element .
Association Selector
Combo Selector
If you use the same style for headings in HTML, you can combine selectors
Pseudo element Selector
Selector for style rules