Since the surf music duo Jan and Dean penned these words for a 1964 hit record, millions of skateboard enthusiasts have taken up their invitation -- not just in the United States but around the world. Kids from California and from Canada, from Indiana and from India, from the United States of America and from the United Arab Emirates have flocked to the pastime, drawn by its heady mix of fun, freedom and challenge.

Like its distant cousin surfing, skateboarding appeals to daredevils, risk-takers and, admittedly, showoffs. The fact that skateboarding originally was called sidewalk surfing reveals the sport’s early craving for teen fad legitimacy. To be sure, both pursuits reward those who have the reflexes of a dragonfly, the agility of an acrobat and the balance of a cat. However, great differences outweigh the two pursuits’ similarities. For one thing, while surfing was originally the exclusive domain of the kings of Hawaii, skateboarding has been the domain, mostly, of ordinary young men and women with an air of good-natured rebelliousness and an outsider’s sensibility.

Some say the first skateboard appeared in the 1950s, when an unnamed teacher broke the handle off some child’s push-scooter, forcing the kid to make the best he could of the resulting four-wheeled platform. Whatever its origins, skateboarding has ridden out several booms and busts over the decades to emerge as one of the most popular recreational sports in the United States, outgrowing any need to evoke comparisons with surfing -- or anything else. It has taken on the cachet of the gaggle of pursuits known as extreme sports, which are undertaken with fierce competitiveness, an intense desire to find the outer edges of performance and an extreme willingness to disregard such preoccupations as gravity and the effect of hard surfaces on falling bodies.

Like any group that wants to stake out its own territory, skateboarders have developed their own language. A "thrasher" is the name given to a beat-up board, or by extension, to the skateboarder himself. The old surf term "gnarly" can be used to describe a difficult stunt or to express enthusiasm and approval. The countless tricks mastered by millions of skateboarders have their own names, including "ollie," "heelflip," "nosegrind," "indiegrab," "180" and "varial." If executed well, fellow skaters will offer their most superlative compliment: "Dude, that stinks!"

After years of trying to ban skateboarders from streets, parking lots, sidewalks and shopping malls -- almost any public space -- many local governments have themselves "pulled a 180," building countless skate parks in cities and towns across the United States. They often have been pushed by sympathetic parents, who have discovered that skateboarding can be a wholesome exercise that cultivates self-confidence, perseverance and camaraderie.

On a warm Thursday afternoon, a dozen or more skateboarders are enjoying the ramps, rails and jumps of one such community-funded skate park outside of Portland, Oregon. They range in age from preternaturally gifted kids no more than 5 or 6 years-old to adults who appear to be in their mid to late 20s. The littlest ones buzz around with the unconscious grace of water bugs. The teens work on more difficult moves, sometimes succeeding, other times falling to the pavement, the impact cushioned by the kneepads and helmets virtually all skateboarders wear.

Connor, a young teenager, tall and quiet, says that he enjoys skateboarding for the emotional "rush" it can offer, the opportunity of "taking it to a new limit." When asked how a skateboarder knows he has found a new limit, he smiles faintly and says, "You crash."

His friend, Zach, a redhead with a sunburned face and a carefree smile, says he got his first skateboard when he was 3. When asked about the sport’s appeal, he grins and says, "It’s fun!" They both talk knowledgeably about their boards, how they choose one that is right for their style and size, and about skateboard attire. They agree that the sagging, oversized grunge look is fading. Tight jeans are in "because they let you see your feet," one says.