You know her type

Since MTV began chronicling the joys and angst of a pretty blond and her posh posse in 2004, Lauren Conrad has emerged as the popular girl everyone wants to be around. If the idea of a cleverly precocious SoCal blond with a fashion obsession and her daddy’s credit card sounds familiar, it’s because Conrad is just the latest incarnation of an archetype that’s been honed over the last 25 years. Call them Valley Girls, Beverly Hills Princesses or Laguna Rhymes-With-Witches, they’re young, privileged -- and almost always blond. They’re the girls you love to hate, with shoes you have to have, ditzes with a hidden streak of resolve that’s underestimated at your peril. One big difference, of course. Conrad, unlike the characters who’ve made “Clueless” and “Legally Blonde” cult favorites, really exists.

-- Adam Tschorn

1982, “Valley Girl”

With the help of daughter Moon Unit, Frank Zappa introduced the rest of the world to the caricature of the shopping-obsessed, mall-dwelling girls of the San Fernando Valley in the song “Valley Girl” with lyrics such as: “Last idea to cross her mind/Had something to do with where to find/A pair of jeans to fit her butt/And where to get her toenails cut.”

The 1983 movie of the same name starred Nicolas Cage and Deborah Foreman (and the priceless tagline: “Life in the Valley: Hair, clothes, and attitude”) playing out a Romeo and Juliet star-crossed lovers routine against the backdrop of the mall. The shallow, hair-flipping, credit-card-wielding stereotype has, like, totally been with us ever since.

1990, “Beverly Hills, 90210”

The show’s 10-year run made it a big pop-culture influence, especially when it came to establishing “blitz shopping” on Melrose and Rodeo as as much a normal part of living in L.A. as smog and traffic. Much of the credit rests with Tori Spelling’s Donna Martin, a character almost as well known for her ability to shop as her ability to hold on to her virginity. Life later imitated art imitating life for Spelling, who later played a thinly fictionalized version of herself in VH-1’s “So NoTORIous,” which included shopping at Kitson boutique on Robertson Boulevard.

1995, “Clueless”

Alicia Silverstone’s Cher Horowitz marked a power shift for the “ditz with a credit card.” Although she struggles to get her driver’s license and shops just to cheer herself up, she’s got skills -- whether it’s making over less-fashionable classmates or using a computerized wardrobe-matching system to coordinate her closet contents. She earns extra points for name-dropping designer Azzedine Alaia during a mugging: “Oh, no. You don’t understand. This is an Alaia.

2001, “Legally Blonde”

Reese Witherspoon’s Elle Woods is a Delta Nu sorority sister bound for Harvard Law School who has to rely on her street smarts to survive -- those streets being Rodeo and Robertson. Less a shopper than a retail “Rain Man,” Woods establishes her cred early on after being lied to by a sales clerk. “You can’t have a half-loop top-stitching on low-viscosity rayon,” she says. “And it’s not new -- I saw it on the cover of last June’s Vogue.” And who else but a die-hard shopper could win a court case based on how to care for a perm and identifying last season’s Prada shoes?