An oldie but a goodie — the back button. The bain of designers, developers and usability experts everywhere. Some love it, some hate it. Here is a roundup of some of the best resources on this topic.

• Web Navigation – a treasure trove of web usability research by Professor Andy Cockburn of the University of Canterbury, Christchurch, NZ. If you are after some hard data rather than speculation, this is a very good place to start.
• Navigation Blindness – Why users ignore navigation and what to do about it.
• Flash Back Button Fix – Robert Penner came up with this back button/bookmark fix for flash a while back.
• Attack of the Back Button – Some words of warning from John Rhodes. While some of the techniques on this page may be a little worn, the sentiments are not.
• dojo.io.bind() Intro – A discussion of the usability issues around Ajax/XHR breaking the back button and a possible solution to the problem within the Dojo toolkit.
• Fixing the back button that AJAX broke – An excellent analysis of the problems of the back button, and the related problem of bookmarks, and a lengthy rumination on some possible solutions.
• Flash Usability – The flash folks have been wrestling with the back button for a bit longer than the Ajax folks. This is a long article with just a little bit on the back button, but some of their suggestions are quite useful.
• Breadcrumb Navigation – With breadcrumbs, users used the back button less frequently, but overall task efficiency was no better.
• Exploring User Mental Models of Breadcrumbs in Web Navigation – Another study on bread crumbs as a solution to back button issues.
• SmartBack: Supporting Users in Back Navigation – excellent overview of research in navigation and some tested ideas on how to inprove back navigation. Could be very interesting for those implementing their own "undo" functions in Ajax.
• Fixing the Back Button and Enabling Bookmarking for AJAX Apps – Mike Stenhouse’s crack at fixing this problem.

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