You can create folders and use keyword tags to categorize your bookmarks.

Once you've created folders, you can:

• Select a bookmark in your list and drag and drop it into a folder.
• Select the checkbox next to each bookmark you want to change and click the Move button on the action bar to move those bookmarks to a selected folder.

Once you've tagged a bookmark, you can:

• Quickly locate it by searching your bookmarks for that tag.
• View all the bookmarks saved with that tag by clicking the Use Tags link in the upper left corner of the Yahoo! Bookmarks Home Page.
• Add or delete tags by selecting the checkbox next to each bookmark you want to change and then selecting Edit Tags from the action bar.