Session 4.1 Quick Checks
1. Text tables and graphical tables. Text tables are supported by all browsers and are easier to create. The graphical table is more difficult to create but provides the user with a cornucopia of formatting options. 
2. A proportional font assigns a different amount of space to each character depending on each character's width. A fixed-width font assigns the same space to each character regardless of width. You should use a fixed-width font in a text table in order to keep columns aligned under all font sizes.
3. The <pre> tag
4. The <tr> tag identifies a table row. The <td> tag identifies individual table cells, and the <th> tag identifies table cells that act as table headings. 
5. The number of rows in a table is determined by the number of <tr> tags. The number of columns is equal to the largest number of <td> and <th> tags within a single table row.
6. The three row groups are the table head, created by enclosing tables within the <thead> tag, the table body created with the <tbody> tag, and the table footer created with the <tfoot> tag.
7. <caption align="bottom">Product Catalog</caption>
This caption must be placed directly after the opening <table> tag.

Session 4.2 Quick Checks
1. <table border="5" cellspacing="3" cellpadding="4">...</table>
2. <td valign="top">...</td> or <th valign="top">...</th>
3. <td align="center">...</td> or <th align="center">...</td>
4.<table width="50%">
5. When the contents of the table do not fit within the cell dimensions or when another cell in the same column has been set to a larger width.
6. <td rowspan="3" colspan="2">...</td> or <th rowspan="3" colspan="2">...</th>
7. <colgroup span="3" style="background-color: yellow"/>

Session 4.3 Quick Checks
1. A columnar layout is a layout in which the page content has been laid out in columns. Text cannot flow from one column to another.
2. A jigsaw layout breaks the page into seperate pieces like the pieces of a jigsaw puzzle. The cell spacing value should be set to 0 pixels.
3. A fixed-width layout sets the absolute size of the page elements, regardless of the size of the browser window.
4. In a fluid layout, one or more of the table elements is sized as a percentage of the page width. The effect of a fluid layout is to set the sizes of page elements based on the size of the browser window.
5. Aural browsers often render the content of the table in the order in which the content appears in the HTML code. If the content is not intelligible when reproduced in that order, the table will be difficult to interpret.
6. <table>
       <tr>
           <td>
                <table><tr><td></td><td></td></tr>
                           <tr><td></td><td></td></tr>
                </table>
           </td>
           <td></td>
      </tr>
   </table>