Hello,
Just wanted to know how do i add static html pages to WordPress? For example, let say i have page products.html, how would i add it to wordpress (any menu, etc) and once added, how do i visit them because wordpress had a typical url structure.
Thanks.
The static page functionality of WordPress is called, cleverly, "Pages." You can read all about them here: http://codex.wordpress.org/Pages
Do you mean Page Templates?: Page Templates « WordPress Codex. You can make a new page template and modify the php and xhtml of it (and add static html), and then use that template when you generate a new Page in the wordpress editor.
If you simply add a static html file to your wordpress directory, it may or may not work, depending on mod rewrite.
To do what you describe, put the products.html page in your public_html directory. Edit your wordpress theme's header.php file to add to the menu section a link to the products.html page. You may have to use an absolute path in the URL depending on how you have things setup.
If you want to retain the wordpress navigation on the products.html so you can browse back to the wordpress parts of your site, you'll need to replicate the header html within that page.
Based on this drawback and depending on your requirements I'd recommend considering using either pages or page templates as suggested in the other answers so that the products page is part of the wordpress layout and you can take advantage of a shared navigation / look and feel etc.