Analyzing your website traffic is crucial. It can help optimize your marketing efforts, improve usability, and most importantly, convert visitors to leads. There are many analytics applications available.
I utilize Google Analytics, which is free and easy to use. It is also integrated into many other Google products including its AdWords advertising platform.
This post at the Google Analytics blog, "Back-to Basics: Non-Brand Keywords," offers a brief and easy tutorial on how to view your non-brand keyword traffic -- this is traffic that comes to your site after entering search terms that do not incorporate your company name or brand name.