Well,

WikiPedia is a good source of knowledge but it is not very simple to use unlike yedda. On wikipedia you cannot ask the questions and cannot interact with the community. While on yedda you can communicate with the community and share your thoughts and knowledge instantly. So yedda is simple to use and you can get instant solutions of your problems.

Google is a good source but you have to search a lot to find your exact information. i always surf the google results and after visiting tons of sites could not find the exact solution Of  course google gives the related answers but not always the exact. On yedda you can ask very specific questions on any topic and can get the right and to the point answer, that you were really looking for.

Yahoo Answers: yahoo answers is a no follow site so you get no reward of giving the solutions to the community in terms of improved website rankings. On the other hand, Yedda is a Do follow site and encourages you to participate more.

thanks.

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