On a new install, all navigation links begin with 'knowledge base'. You're likely to want to customize this to something appropriate for your website. To do so, go to your admin panel and click 'manage languages'. Then use the filter option at the top to search for the language item with the content 'Links Directory'. This item will be named navorigin. Change it to what you desire. Now, when you view pages again that have navigation links, they will have your title in place of where 'Links Directory' used to be.

To change what shows up in the title bar of your web browser on each page, again go to 'manage languages' and this time click on 'page titles' from the list of sections. This will show you all the various titles. Change those you wish to change and click the submit button.

If you want the order of the title parts reversed, so that it's "Cateogory: Links Directory" instead of "Links Directory: Category", see the page titles schema at Admin Panel -> Settings -> General.