Search Engine Optimization (SEO)

SEO is an acronym for "search engine optimization" or "search engine optimizer." Deciding to hire an SEO is a big decision that can potentially improve your site and save time, but you can also risk damage to your site and reputation. Make sure to research the potential advantages as well as the damage that an irresponsible SEO can do to your site. Many SEOs and other agencies and consultants provide useful services for website owners, including:

• Review of your site content or structure
• Technical advice on website development: for example, hosting, redirects, error pages, use of JavaScript
• Content development
• Management of online business development campaigns
• Keyword research
• SEO training
• Expertise in specific markets and geographies.

Keep in mind that the Google search results page includes organic search results and often paid advertisement (denoted by the heading "Sponsored Links") as well. Advertising with Google won't have any effect on your site's presence in our search results. Google never accepts money to include or rank sites in our search results, and it costs nothing to appear in our organic search results. Free resources such as Webmaster Tools, the official Webmaster Central blog, and our discussion forum can provide you with a great deal of information about how to optimize your site for organic search. Many of these free sources, as well as information on paid search, can be found on Google Webmaster Central.
Before beginning your search for an SEO, it's a great idea to become an educated consumer and get familiar with how search engines work. We recommend starting here:

• Google Webmaster Guidelines
• Google 101: How Google crawls, indexes and serves the web.

If you're thinking about hiring an SEO, the earlier the better. A great time to hire is when you're considering a site redesign, or planning to launch a new site. That way, you and your SEO can ensure that your site is designed to be search engine-friendly from the bottom up. However, a good SEO can also help improve an existing site.
Some useful questions to ask an SEO include:

• Can you show me examples of your previous work and share some success stories?
• Do you follow the Google Webmaster Guidelines?
• Do you offer any online marketing services or advice to complement your organic search business?
• What kind of results do you expect to see, and in what timeframe? How do you measure your success?
• What's your experience in my industry?
• What's your experience in my country/city?
• What's your experience developing international sites?
• What are your most important SEO techniques?
• How long have you been in business?
• How can I expect to communicate with you? Will you share with me all the changes you make to my site, and provide detailed information about your recommendations and the reasoning behind them?

While SEOs can provide clients with valuable services, some unethical SEOs have given the industry a black eye through their overly aggressive marketing efforts and their attempts to manipulate search engine results in unfair ways. Practices that violate our guidelines may result in a negative adjustment of your site's presence in Google, or even the removal of your site from our index. Here are some things to consider:
This article is taken from- http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=35291