What's Christianity All About?

In days gone by, most people living in Australia would have produced a reasonably good off-the-cuff answer to this question.

But in our present, multi-cultural, increasingly atheistic nation, there are many people for whom this question would draw a blank.
Additionally, as a consequence of the behaviour and commentary of some people who identify as Christian, others who might claim to know the answer could be well off the mark.

So how would we answer?
And if the question was raised in casual conversation, how would we answer in less than the 30 seconds we might be expected to give a response?
 
I would like to give all Christians reading this post a challenge.
Firstly, let's be sure we have a Biblically based idea of what Christianity is all about.
Then try to write an answer to this question that could be spoken, at normal casual conversation speed, in less than 5 minutes.
Then review, edit and re-write the answer so that it could be spoken in less than 2 minutes.
Then review it again and re-write it so that it could be said, conversationally, in less than 30 seconds.
Then memorise and practise it and be ready to use it whenever God produces the opportunity.

If the question is raised in casual conversation keep in mind that our answer, as well as being accurate, needs to be interesting enough to prompt our questioner to keep the conversation going in that direction.

I would love to see some 30 second answers posted in the Comments section below (as an anonymous commenter if you would prefer that).

By the way, I have started my 30 second response with ... "It's all about being a follower of God's Son, Jesus Christ ... "

Blessings, Barry