Why has Harry cast such a spell?

Millions of fans are expected to line up to purchase the long-awaited 608-page sixth installment Saturday at 12:01 a.m. local time, one of the most highly anticipated book launches in publishing history.

Then there are also those planning one of hundreds of parties leading up to the witching hour.

And what of the mayor of one small Ontario town who will temporarily rename New Hamburg to New Hogsmeade Friday night?

Indeed, the numbers speak for themselves; more than 265 million of J.K. Rowling's Harry Potter books have been sold in 200 countries and published in more than 60 languages.

Canada's dominant book retail chain Indigo expects to sell almost 200 copies per minute within the first 24 hours following the release.

To put the numbers in perspective, if the bookstore chain's copies of the Half-Blood Prince were stacked up they would be 100 times higher than Toronto's landmark CN Tower.

So why is the world so wild about Harry?

"As Harry grows up in the books, the readers are aging, so the series has got a longer longevity and shelf-life with audiences," Fionna Boyle, author of An Unofficial Muggle's Guide to the Wizarding World told CTV.ca.

Even so, not all fans started young.

"I know more adult Harry Potter readers than children," Boyle said, noting her father, who is in his 60s, will likely be lining up at midnight for his own copy of the book.

Though the books are widely considered to be children's literature, both young and adult readers alike are eagerly anticipating the latest installment.

Indeed, there have been other popular children's series exploring the world of fantasy, such as the Artemis Fowl series or the Lemony Snicket's A Series of Unfortunate Events books; but none have come as close to bewitching the masses as Harry has.

The appeal does not only lie in the supernatural, Boyle believes.

When the original Harry Potter book made its debut in 1997, the first generation of fans was the ideal target audience to become enchanted with a world complete with ghosts and flying owls.

These days, those readers have grown up. But for many, the books exert the same hold as Rowling's series becomes increasingly dark and explore weightier topics such as death and betrayal.

"Rowling is exploring themes that people can certainly identify with -- the struggle to find out who you are, to be accepted by your peers and worry what they think of you, or the struggles with your family, in school, and relationships," she said.

"Everyone can identify with the universal themes that have nothing to do with magic and everything to do with reality."

Still others revisit familiar books and characters such as Harry Potter for the same reason they seek out their worn-out childhood stuffed animals -- they promise a sense of familiarity and security.

"This offers enormous consolation," John Cech, director of the Center for the Study of Children's Literature and Culture at the University of Florida in Gainesville, told The New York Times.

"And that is more important in a world that's much more fragmented and more fragile."

So while it's not magic that has millions of people around the world caught up in the pages of Harry Potter, it seems that even if it were wizardry, his fans would be happy to be under his spell.