When is Diwali 2015? When is Deepavali 2015? What is Diwali/Deepavali?

When is Diwali 2015? When is Deepavali 2015? What is Diwali/Deepavali?
http://www.etcpb.com/when-is-diwali-2015-when-is-deepavali-2015-what-is-diwalideepavali/
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