Jesus Christ! You don't know what the Immaculate Conception is?
What it certainly isn't is anything to do with how Christ was conceived - that was more of a Miraculous Conception. No, the Immaculate Conception has its origins in that most windswept and interesting thing in the world, Catholic dogma.
Yep, those same articles of faith that tell us that Mary's mother was called Ann also dictate that the world's most famous virgin was kept free from original sin at the time of her conception - thus meaning that she was every bit as blameless as her child.
And if you're wondering where all this is mentioned in The Bible, it isn't. That's how Catholic dogma works. Likewise, the Assumption - the bodily taking up of Mary to heaven at the end of her earthly life - isn't to be found in scripture.
As you've probably figured out, the above is the reason the Roman Catholic Church makes such a big fuss about the Blessed Virgin. As the writer-director John Waters explains in his hysterical one-man show This Filthy World, there are some who take their worship a few steps too far, preferring to dedicate themselves to the carpenter's wife rather than her somewhat more celebrated son.