SEO is an abbreviation for “Search Engine Optimization.” A website that is optimized to attract traffic from the search engines (Google, Yahoo, Bing etc) is an integral part of any business. More traffic= More business= More $$$
When you search for a product or service on Google for instance, it shows you the top results.
How good would it be if your business showed in the top results? An optimized website will greatly increase the probability of this happening.