For a language that emerged from academia--a place steeped in data--it's not surprising to find that HTML supports a set of tags for data tables that not only align your numbers, but can specially format your text, too.
Five tags enable tables, including the <table> tag itself and a <caption> tag for including a description of the table. Special tag attributes let you change the look and dimensions of the table. You create a table row by row, putting between the table row (<tr>) tag and its end tag (</tr>) either table header (<th>) or table data (<td>) tags and their respective contents for each cell in the table. Headers and data may contain nearly any regular HTML content, including text, images, forms, and even another table. As a result, you can also use HTML tables for advanced text formatting, such as for multicolumn text and sidebar headers (see Figure 2.5). For more information, see Chapter 11, Tables.