How to Put Black Line in CSS. The HR tag enables you to include a gray horizontal rule in your Web page that is useful for dividing sections of data to keep things organized or for aesthetic purposes.

CSS, or Cascading Style Sheets, defines the look and formatting of that HTML. Both are essential to coding your own website, and here's how to get acquainted with them.

Learn HTML and CSS online for free, and use them to create webpages or move up in your career.

SEE: Learn how to create tables using HTML. (TechRepublic) How to align table margins in Word When you have a table that doesn’t spread from the left to the right margin, you might want to align it.