this is a small tip on the use of bookmarks (or anchors)
Bookmarks are used to force the browser to focus on the page area where the bookmark itself is placed. For example, you can create a TOP at the bottom of your page, if the page is very high, and link it to a bookmark which is at the top of the page. By clicking on TOP your browser will go to the top of the page without need for scrolling.
What is not so evident at a first glance, is that there can be links between a page and a bookmark placed in another page. And this link can open in the same or another window or in an i-frame, allowing for small customised photo galleries or option querries to be carried out. If you're interested, see how this can be done here.