It has been compared to shuffleboard (for its sliding projectile), chess (for its strategy), golf (for its precision) and watching paint dry (for the leisurely trip of the rock down the ice).
With the return of the Winter Olympics, many Americans are trying to get a handle on curling.
But for members of the Potomac Curling Club in Laurel, this sport of granite rocks sliding down icy sheets surrounded by frantic sweepers is their passion.
For them, the Olympics means more games to watch on television, more media coverage and more people saying, "Oh, is that what you do?"
But most of all, club members hope it will mean more curlers.
Curling became an Olympic medal event in 1998 but it started gaining recognition among Americans during the 2002 games in Salt Lake City, when cable television started showing the games.
That year, the Potomac club's open house drew 700 people over two days, said its president, Dominique Banville. The club's membership has tripled to about 180 since 2002, she said.
The Potomac Curling Club, which runs the National Capital Curling Center in Laurel, is holding an open house next week. Like many clubs across the country, it wants to capitalize on the sport's two weeks in the spotlight.
The club will offer drop-in lessons from 7 p.m. to 9 p.m. Thursday; from 1 p.m. to 4 p.m. Saturday; and from 9 a.m. to 12 p.m. Sunday.
"We are gearing up for a lot of people," Banville said.
She said curling does not take a long time to learn, and it can be done by people of all ages and athletic abilities. But "it takes a lifetime to master it," she said, "and I think that's what is attractive to people."
Along with more attention, many curlers hope this Olympics will bring the sport some long-overdue respect.
Curling is believed to have begun on the frozen lochs and marshes of 16th-century Scotland and migrated to the United States in the 1830s.
Banville admits that for those who do not live in wintery states like Wisconsin and Minnesota, the first reaction to seeing the sport is often laughter.
But, she said, "people start watching it and they are amazed by the game itself, the strategy and what those guys and gals can do."
What they can do, with lots of practice, is get a 42-pound polished granite weight to slide about 93 feet to the center of a 12-foot-diameter circle - called the "house" - and not beyond.
The thrower pushes off from a block with his or her leg and glides forward - with the help of a Teflon pad on the player's shoe - in a crouched position while holding a handle on the rock.
At the "hog line," the thrower lets go with a twist of the wrist to create the "curl" or rotating motion.
According to John Bittner, a past club president and curler for 43 years, until the 1950s, it was most common for a thrower to swing his or her arm like a pendulum to release the rock. But a Canadian competitor introduced the sliding release and it was widely adopted.
For amateurs, it also ensures fewer dings in the ice and less danger of injuring oneself, Bittner said.
The hog line, at which the stone must be released, was added when at least one competitor tried to slide all the way to the house and leave the rock in the center, he said.
The sweepers are there to control the speed of the rock. Their brooms - sometimes made of horsehair, but more commonly foam pads covered with synthetic material - create friction, which melts a thin layer of water on which the stone can glide.
After each team throws eight rocks, whichever team has a rock closest to the center of the house wins that "end," or round of play. They get one point for every rock that ends up closer to the center than any competitor's rock.
Rocks also are used to knock competitors out of the house and to block other rocks that are in a good position.
Players say curling is a social activity, with a tradition of good sportsmanship, of self-policing and of the winners buying the drinks.
"It is really civilized," said Laurie Baty of University Park, who joined the club in 2002. In addition to shaking hands before and after the game, "we compliment each other on a good shot, even if it's the other team."
Julie Stewart and her fiance, Ben Meddows, both of White Marsh, got interested in curling during the 2002 Olympics and joined the Potomac club in January.
"It looked intriguing, " Stewart said. "It really is addictive. We want to play more, we want to get better. We're competitive people."
Thursday's drop-in session drew a group of student filmmakers from John F. Kennedy High School in Silver Spring who were inspired by the Olympic coverage to find out what curling was about.
"It was really fun, but it was very slippery," said Kevin Watkins, a senior from Wheaton.
He admitted he was surprised at the complexity of the game.
"There is physics and math ... involved," he said. On television, "they make it look so easy."
According to Bob Pelletier, a past club president and board member of the United States Curling Association, there are more than 15,000 curlers and 135 clubs in the United States, with the highest concentration in the north-central states.
The Potomac Curling Club is one of two in Maryland, he said. The two clubs that are the next nearest are in Pennsylvania and New Jersey.
Pelletier's club has several competitive and social leagues and youth programs. A few members compete at the national level.
Though curling has become more familiar, Banville said, "It's still interesting how when you talk about curling ... [people] want to laugh. As a curler I don't understand that."
She added: "The more we talk about it the more we'll educate people. I think it will be good for the sport."
For information, go to curldc.org or call 301-362-1116.