You're probably using them already. What most browsers refer to as 'bookmarks', Microsoft has renamed as 'favorites' (with that horrid American spelling)
On my browser (Firefox) I can click on
Bookmarks>Bookmark This Page
in order to store a website's address for future use.
With Internet Explorer, clicking
Favorites>Add To Favorites
does exactly the same thing.
So when you visit a page that you like (and might want to re-visit) you can bookmark it (= add it to your favorites). To revisit the site you simply click on Favorites and then on the name of the site.
If you find that you've got a lot of bookmarks (= favorites) you might want to organise them into folders. To find the instructions for doing so (in Internet Explorer) click on Help > Contents and Inde, select the Index tab and enter 'favorites' into the search box.
Chris