The Yippy search engine has had a long and torturous history. We had a great little search engine called Clusty, which then morphed into Yippy. It used to have a family friendly mission statement, only giving access to material that was appropriate for all ages, and to promote conservative values (whatever they are!) Almost overnight it went from being a really useful engine as Clusty into a train wreck that was Yippy. Thankfully it then disappeared off our radar, and we thought that it had disappeared for good.
Until today, when it has returned. It's no better than when it left us, quite frankly. It has, interesting, got rid of the whole family friendly approach, given that it was perfectly happy to return lots of hits on my quite frankly extreme pornography search, so we can draw a line through that particular selling point. It does however still cluster results - that is to say, that if you do a search for 'Everton', it will return clusters for 'Football', 'Club', 'Fixtures' and so on. You can then click on the appropriate cluster and drill down into the results, so that's actually quite useful in its own right.
However... you can't go back to view a previous result. It's just gone. You have to redo the search from scratch. There's also no advanced search option, although there are some advanced search functions - I could do a search for title: but it wasn't interested in doing a search for site: So I think I'm supposed to just go through each potential search function in turn to find the ones the work. Not terribly helpful.
There also isn't a way to search images, news, videos, or anything else from what I can see. We're stuck with just a straight forward web search. Seriously, why would anyone bother to use such a archiac waste of space? Even then, their numbers count is off - I did a search which gave me 4 results, but there was only one available for me to view; filetype:pdf dog Now, I know that Google gets confused over numbers, but at least they're usually working in hundreds of thousands, if not millions.
In summary, Yippy is a complete waste of space, and more importantly a waste of your time. Simply ignore it and carry on using a decent clustering search engine like Carrot2 at http://search.carrot2.org/stable/search