Cascading Style Sheet(CSS):
HTML is used to structure the content.
CSS is used for formatting structured content.
It defines layout of HTML documents. For example, CSS covers fonts, colours, margins, lines, height, width, background images, advanced positions

Example :
(1)Clicking the Start button, typing "Notepad" in the search field and pressing "Enter"
Click "File" and "Save as" from the main can give the name of your file .followed by the extension ".css" and choose "All Files" as the Save as type.(eg: mycssfile.css)
CSS style rules all consist of a property and a value; the property identifies what you will be changing, such as the background color. The value gives the name or numeric value of the color used. The syntax is {property: value; }
eg; { background-color: blue;}
he CSS file name should be directly related to the website in question in order to assign style rules. For example, if your website domain name is, use "mycssfile.css" as your CSS file name.
(3)Now open the HTML file for your website in Notepad.Enter the following code before the "head" end tag: 
< link rel="stylesheet" type="text/css" href="mycssfile.css" >
This tells your web page where to look for definitions of your CSS rules for this website.

By this way a CSS can be created.
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