SEOUL -- Jeon Hye Eun, a 27-year-old hotel-marketing executive, is taking time off this week to do her holiday shopping. After all, Saturday is Pepero Day.

Like any South Korean, she is expected to give away boxes of cookie sticks and other skinny confections. While the U.S. and some European countries use the date to commemorate the sacrifices of war, in South Korea Nov. 11 is a late-year celebration of love and friendship that costs less than Valentine's Day and is "fun, cheap and feels nice," she says.

It started with the Pepero, a long, thin cookie popular in South Korea coated with chocolate or other flavors that, befitting the date of 11/11, resembles the number one. Lotte Confectionery Co., Pepero's maker, sells nearly two-thirds of its annual volume of Pepero snacks in the two months leading up to Nov. 11, and Pepero cookies accounted for 44 billion won ($47 million) of Korea-based Lotte's 1.15 trillion won in revenue last year.

But it isn't just Pepero. The best shelf space in South Korean groceries and convenience stores from mid-October is given over to dozens of snacks and baked goods in long, thin boxes stood upright. Makers of food that isn't long or thin, such as Tootsie Pop lollipops and Ferrero Rocher chocolates, repackage their products into tall boxes all the same.

Korean bakeries this week are selling baguettes dipped in chocolate and making their own long cookies. Credit-card companies have special promotions in early November that include gift sets of Pepero cookies. Even bookstores have gotten in on the act, packaging snacks, calendars and office supplies to fit the unofficial holiday.

During the lunch hour Thursday, businessman Jung Sung Woo, 41, bought several boxes of Pepero for his colleagues from a big display outside Kyobo Book Centre, South Korea's largest bookstore, in downtown Seoul. "It'll make them happy," Mr. Jung said.

While Lotte clearly encourages Pepero Day celebrations now, the company says it had nothing to do with the holiday's creation. That dates back to about a decade ago, Lotte says, when retailers in the city of Busan noticed middle-school girls exchanging boxes of Pepero cookies as friendship gifts around Nov. 11.

In recent years, such gift-giving days have emerged in almost every month in South Korea. Valentine's Day in February is followed on March 14 by White Day, which is similar to Valentine's but with bigger gifts from the men. Other months have Teachers' Day and Children's Day.

Marketers have invented holidays for teachers and bosses and secretaries in many cultures. But Korea has a special flair when it comes to gift-giving days. It boasts days for couples to give each other diaries and exchange silver, among others. Rose Day is also called Yellow Day for single people because they're supposed to eat yellow curry rice. The protocols are particular, too: chocolates to men on Valentine's day, mints and chocolates for women on White Day.

Ham In Hi, sociology professor at Ewha Womans University, attributes the popularity of such days to the rise of individualism and a diminishing reliance on families in Korean society. "People give more meaning to meeting new people they don't know. So they give gifts to each other," she says. "It is a way to develop relationships."

Lotte noticed the 11/11-related surge in Pepero sales a few years ago, it says, and decided in 2002 to start offering its cookies in a broader array of packaging for the event. It also combined Pepero cookies with other cheap gifts, such as pens and key chains. In 2003, the company added a Pepero Web site complete with a countdown and theme song, which has changed every year since.

Other cookie and candy makers jumped in. Orion Corp., a top rival to Lotte, tried for several years to become part of the Pepero Day market with some of its own goods, which include marshmallow pies and chocolate-chip cookies. For this year's 11/11, Orion launched a Pepero-like cookie called "Beauty Stick" and cranked up promotion by placing pictures of a popular band on packages and creating a blog devoted to it.

In Japan, retailers for several years have been promoting Pocky snacks, the long cookies and pretzels that were Lotte's inspiration for the Pepero back in the 1980s, for an 11/11 celebration. The idea hasn't become as popular there.

Not everyone in Korea is a fan of Pepero Day. According to the Ministry of Education, some schools, disapproving of the commercialism, have banned children from bringing the cookies for gift exchanges this year.