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In most tables a cell occupies space within a single column, but occasionally you may want a row to be wider than one column. Rows and columns can be enlarged by combining them with adjacent cells to group information. Further, you can align data, add hyperlinks, and add images to make your table visually appealing.
Spanning [...]

When you define an embedded style for a tag, you can no longer use the default style of the tag on your Web page. To be able to do so, you can define a class for the tag instead. A class allows you to apply several formatting styles for different occurrences of the same tag. [...]

A Web site is a collection of Web pages.

Style sheets allow you to separate the content of a page from its design. A style sheet is a set of rules that define the formatting of HTML tags on a page. Using style sheets, you can control how a Web site is rendered, including the margins, indents, and text backgrounds without changing the HTML [...]

A Home page is the first page that appears in the browser when you access a Web site.

To maintain consistency between pages in a Web site, it is useful to include more than one way of applying styles to a page. However, multiple style sheets can contain conflicting style information. In these situations, the browser decides which style to apply by using the cascading order of styles.
Cascading order of styles
You can use [...]

A linked style sheet is an external file that contains only the style definitions as defined within the STYLE tags in the head section for embedded styles. This external file has a .css extension. The first line after the starting STYLE tag is not executed. It is advisable to add a comment as the first [...]

Linked style sheets are one of the most powerful ways to use styles on your Web pages. They provide the ability to create one style sheet that affects multiple pages. You can change the entire look of your site by modifying just a few lines of code in a single style sheet.
Linked style sheets
A linked [...]