The id selector uses the id attribute of an HTML tag to find the specific element.
An id should be unique within a page, so you should use the id selector when you want to find a single, unique element.
To find an element with a specific id, write a hash character, followed by the id of the element.
The style rule below will be applied to the HTML element with id="p1":
#id { css declarations; }
<html> <head> <style type="text/css"> #paragraph{ font-size:35px; background-color:#0000FF; color:#00FFFF; padding:5px; } </style> </head> <body> <p id="paragraph">Welcome to CSS Tutorial</p> </body> </html>