PEORIA, Ill. -- Clea White stands back and surveys her customer's features. She eyeballs the contours of the woman's scalp and the thickness of the woman's hair, then she takes the sharp edge of a plastic comb and slices a line through the center of the woman's head.

It is, from all appearances, a simple line -- slightly off center at the woman's hairline, over the crown of her head, down to the nape of her neck. White parts the hair quickly, almost intuitively, with no thought of marking, measuring or the subtle elegance of her move.

"The parting, that's what makes braiding," she said. "To me, once you have that perfect part, everything else falls into place."

Braiding comes naturally to White, who does hair at Winters Barber Shop and Beauty Salon on Peoria's South Side.

She had taught herself the fundamentals by the time she was 8; she built upon the basics until her skills multiplied. Now she does box braids, French braids, micro braids, cornrows, braids with human hair extensions, braids without. She keeps a virtual album of her most intricate braided designs, typically laid out on the heads of young men conscious of cornrow fashions worn by NBA stars like Allen Iverson.

But if the braiding comes naturally, parting and sectioning to make the braids is math from the roots. Few braiders, or their clients, ever thought about the math involved in braided hairstyles until about a decade ago, when a Milwaukee mathematician began making the connection.

"The mathematics itself is in the styling," said Gloria Gilmer, an educational consultant who has previously taught math at several colleges. "You can't help but look at these hairstyles and see the geometry."

Gilmer, a founding member of the International Study Group on Ethnomathematics, wasn't as interested in hairstyles as she was in exploring how different cultures integrate math concepts into everyday life.

"Nobody ever tells you math is natural," Gilmer said.

Back to Clea White and her customer, 73-year-old, tender-headed Mary Cornish.

White's fingers fly as she laces cornrows down and around each side of Cornish's scalp. When she finishes, each row curves around Cornish's head, evenly spaced and parallel to every other row in a pattern perpendicular to that first, central part.

Subconsciously, she has calculated how wide each cornrow should be, how long each strand of hair should be and where each braid should end.

Math was White's favorite subject in school. A 1996 graduate of Manual High School, she loved fractions and algebra. Ironically, she says, her passion for math class "fell off" when she got to geometry.

Unlike White, fellow braider Ricci Boudreaux-Harris, 40, of Peoria, Ill., said math never appealed to her.

"I hate math, I really do. But if I have to deal with it, I'll deal with it."

She uses a small hand mirror, along with a big mirror, to part her hair into sections.

"Once I start one part, the design takes over," she said. "I don't pay attention to it; I never thought it was a big deal."