SEO is the art of getting your website ranking in the search engines. Once you have a high rank in the search engines results pages, It means the Search Engines think your site is extremely relevant, and an authority, on its subject matter, visitors will more likely to have a look on your website ,and then more traffic will come to your site.
Good SEO relies on two factors: on-site optimization and off-site optimization. On-site Optimization means good content, keywords and clear paths. Off-Site optimization is quite simply boils down to back links, which are simply links from other websites to yours. SO we talk about the here is on-site optimization. And there are a number of Joomla Extensions that will help you and they are free.
JoomSEO is a Search Engine Optimizing (SEO) bot making Joomla content more Search Engine Friendly(SEF). JoomSEO dynamically creates meta keywords, meta descriptions, changes the title on the fly (Adds the sitename for Joomla 1.5), adds heading tags to content titles and more. JoomSEO is highly customizable and saves the hassle and time of manually adjusting these settings, keeping all words and descriptions relevant for the search engines, improving ranking and accessibility. JoomSEO has many options giving you control and flexibility.
2 SEF Patch
It lets you manually enter Title Tags and all Meta information for articles, front page and all menu items. But it also have the Ability to have custom title fields (optional to include the site name or not) and to control the other meta tags settings such as keywords and descriptions – it gives you the option to choose combinations options such as whether to display the default Joomla! descriptions if no content description is available. It some other control settings over the Robots tag, how Google cache your pages and others.
Sh404SEF rewrites Joomla URL to user-friendly format (SEF URL or URL rewriting). It is also a security component and manages title and meta tags: automatic tags, or manual for every page. Sh404SEF can improve your search engine ranking and get more traffic to your site. It can also protect your site from common exploits and improve site navigation and HTML best-practices.
Xmap is a Site map generator component for Joomla, it’s based on the popular Joomap component. Xmap allows you to create a map of your site using the structure of your menus.
Joomap is a sitemap component for Joomla that shows the normal Menu Structure, Content Categories, Sections and Virtuemart Categories in a hierarchical tree or a Google Sitemaps list.
With this tools and using them in combinations you can Optimize Joomla 1.5 For Search Engines. And you will benefit most for the least effort.