If frames are used for the sidebar, consider the WBP recommendations that frames should by used judiciously. In the past, frames have been used as a method to lay out pages, so repeated elements are available on every page. For example, a sidebar in a frame on each page could contain navigational elements. However, WBP recommends avoiding frames altogether. Avoid using frames.
Frames make it difficult for the user to bookmark a specific page.
Frames also make the process of printing the page confusing for the novice user. Coding the HTML to drop the correct page into the appropriate frame may become muddled, making it more difficult for search engines to find the pages. And JavaScript rollover menus may not function correctly as the user's cursor travels from frame to frame. Most important frames do not comply with the disabilities act. These issues are a few of the reasons why we do not recommend the use of frames.