Catalog update
Estimate how often catalogs are updated, based on studies and search engine help pages. Better search engines will constantly update their catalogs. Since the majority don't date their catalogs, it can be hard to tell how old the catalogs are.

Spam penalty
Several engines will penalize sites using a variety of techniques to "spam" the engines and improve their position. One common technique is "stacking" or "stuffing" words on a page. This is where a word is repeated many times in a row.

Directories
Unlike search engines, directories are created by humans. Sites must be submitted, then they are assigned to an appropriate category or categories. Because of the human role, directories often provide better results than search engines. Yahoo is an example of a directory.

Design plays no role in how a site appears in a directory, with the only exception being that a good site, with good content, might be more likely to influence a review to include the site. For the most part, things that are useful for improving a site's appearance in a search engine have nothing to do with improving a site's listing in a directory.

Page layout
It is important to understand that the way a site appears in a search engine can be greatly influenced by design. Page titles, body copy and other elements (such as "META" tags -- more on these important elements in a moment) all play a role. A common misconception about search engines is that they index all of the text within your Web pages. Experience has taught us that search engines like to index text that appears at the top of a page. Well, the <TITLE> tag appears at the top of the page, so we can use this to our advantage.

The page <TITLE> is by far the most powerful positioning element for search engines. Robots consider the <TITLE> of a page to be the most telling description of the content of a page. A search engine's robot or "spider" will look at this first, and if it finds a keyword here, your page will be displayed above other pages which only have the keyword in the main body of text. Therefore, choose your <TITLE> keywords carefully: use a few of the most powerful ones and don't make your <TITLE> as long as your arm just to fit all your keywords. By making each page title descriptive, and by including key words between the title tags, you can improve your search engine ranking in virtually all of the search engines. Here's an example:

[There are trade-offs. Titles are also the default name for most favorite links, when saved in a browser. Very long titles can often be quite unmanageable for users, even if they're great for being indexed in search engines. --DG]

Some page layouts do not lend themselves to including a paragraph of text at the top of each page. This may be because the page layout is graphical, or may use an image map as a navigator. Search engines tend to like text at the top of the page. We can use a hidden text block to accomplish this. A hidden text block is just what it sounds like: a block of text that's not displayed by the browser. If you're already familiar with META tags, you might think, "This sounds just like the META tag, doesn't it?" Well, it sort of works like a META tag, without the typical HTML tag brackets around it.