This is particularly important for dynamic database driven sites like blogs and directories, where the same error can be repeated on hundreds of pages.

These days the search engines are can deal with quite a few validation errors, but is it worth the risk? The code of his web pages is one thing a webmaster has complete control over, so it is worth making sure they are error free and as well optimised as possible.

The W3C HTML Validator is the place to go to check a page. Popular HTML editors such as Dreamweaver usually have built in validation tools and you can also find some good add-ons for FireFox that do the job.

Those key phrases need to be in your web pages for the search engines but without making your copy completely unreadable for human beings.

Here are a few basic tips for achieving this:

Limit use of words like ‘We’ and ‘it’

Instead, repeat the name of the company/ site or what the company/ site does. For example, instead of “We provide plumbers in the….” use “Gifford Plumbing Services provide plumbers in the…”

Search engines ignore punctuation

This means, for example, that the words at the end of a sentence are combined with those at the start of the next sentence to form phrases – “We provide all kinds of plumbing. In Kent, the areas we are able to cover include….” yields the phrase plumbing in Kent.

Use Title and Alt attributes

You can be a bit more liberal with keywords and phrases in the unseen parts of your code, such as Title and Alt attributes, but don’t stuff them and remember they are important for accessibility. The Title text for a button should be “Button: Homepage for Gifford Plumbing Services” not just “Button: Homepage”

The Title and Alt attributes can also be used to include phrases and keyword variations that are difficult to include in the normal content. Don’t just repeat keywords and phrases that are in the anchor tags.

Use named anchors

You can also add named anchors to your page, whether you use them or not. These are another opportunity to add keyphrases without making your on-screen copy unreadable. (Using them in internal links also means you can include keyphrases in the URLs).

Use keyphrases in filenames

Make sure the files in your site have keyphrases in the filenames. This is another good way to include keywords which may be difficult to include in normal text.

Break up copy with headings and bulleted lists

This is good practice for writing on the web anyway as it makes a web page more readable. It also means you can repeat and emphasise important information, which naturally contains keyphrases.

Pros:

1. A directory opens up more opportunities for promotion on related sites such as forums, blogs and other directories. There are webmaster forums such as Vilesilencer, dp and v7n where you can announce a directory (as well as niche specific forums), and ‘directories of directories’ for listing your directory.
2. If you can make it a quality resource, a directory can be an additional source of traffic and possibly revenue if you charge for listings. This is especially true if you set up a directory relevant to your niche rather than a general directory. You may find other sites link to it as well.
3. A well managed and structured directory can help you achieve higher search engine results by adding many themed pages to your site. The number of pages indexed is an important factor in ranking highly in search engines. (Although you need to take into account Con number 2 below).
4. A directory can help you build up a list of contacts within your niche.

Cons:

1. You need a little bit of technical knowledge (PHP and MySQL) to set up a directory, especially if you want to modify it. (Writing and maintaining a directory by coding static HTML would be a very tedious job).
2. There is a big up front workload in planning and setting up a directory. You need to spend time creating an original category structure, writing good category descriptions to avoid duplicate content problems and promoting it.
3. Although you don’t have the ongoing work of creating content (those who submit to your directory do that for you) you do have to spend some time on maintenance – reviewing submissions, deleting spam, updating the script etc.
4. The biggest danger in setting up a directory is in creating duplicate/ low quality content. These pages can dilute the PageRank of your site and make it less trusted in search engines (see this post on seobook.com).

So, keep the directory ‘niche’, i.e. only include categories related to the main site theme. General directories are harder to maintain and can easily become spammy. Try to avoid duplicate content issues by encouraging quality submissions with well written descriptions, writing unique descriptions for the catagories and by varying other elements on the page – have different headers, footers and sidebars for the directory, or even for specific categories.

There are a number of free directory scripts to choose from:

• PHP Link Directory
• Site Sift Listings
• Index Script
• Esydicat Directory Script
• IndexU

Of these, PHP Link Directory is probably the most popular (it is used to power the SEO directory on this site) and there is plenty of extra information and support on their forum.