An accordion is a stacked list of item references (e.g. labels or thumbnails), where each item can be "expanded" or "stretched" to reveal more content associated with that item. Typically only one item can be expanded at a time, and expanding a second item causes the last opened item to be closed.
I recently found a great write-up about SEO and anchored links . In particular, I found the following to be very helpful: For longer or more complex pages, search engines frequently create ...