We're smack-dab in the middle of summer, and if those huge sweat stains aren't enough to convince you, just check out the marquee at your local multiplex. There are a dozen or so films competing for your ticket dollahs, y'all, nearly every one of them snugly fitting into the confines of what have come to be known as "summer movies."

What makes a film a summer movie as opposed to just a movie, aside from being released between Memorial Day and Labor Day?

Basically, a summer movie needs to avoid being challenging in any way. It should fry your brain like the sun burns your skin. It should go down as easy as a slushy chasing a melted Milk Dud. It should be a cinematic vacation from edification, depression and introspection. And it usually fits into one of the following categories:

The Franchise Continues

Believe it or not, there was a time, long, long ago, when "sequel" was a dirty word in Hollywood. Back when most films were more about story than characters, the idea of continuing a tale that had a finite ending smacked of crass, unoriginal opportunism. These days, crass, unoriginal opportunism is a driving force in Hollywood. The studios rely on pre-sold brands, such as this summer's undisputed blockbuster, "Pirates of the Caribbean: Dead Man's Chest," to build excitement for the all-important opening-weekend box office. Of course, franchises burn out after awhile, as the dismal showing of "Mission: Impossible III" proves.

The Comic Book Movie

Part of the appeal to Hollywood of comic book films is that there's already a rabid fanbase built-in before the actors even go before the cameras. Sometimes that pays off big ("X-Men: The Last Stand"), and sometimes it doesn't ("Superman Returns"). But with "Ghost Rider," "Iron Man," "Wonder Woman" and "The Flash" as well as sequels for Batman, the Hulk, Wolverine and Spidey all coming down the pipe, the fanboy parade doesn't seem like it's going to end any time soon.

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From the Small Screen to the Big

Even more recognizable to the general public are classic television shows, often burned into pop culture consciousness deeper than the names of some first cousins. The big-screen TV adaptation is another once-derided lowbrow concept that has become so commonplace as to be an accepted summer genre. And so, with a completely straight face, Hollywood presents "Miami Vice." You thought the well of comics being adapted was deep? Just wait until we get "Diff'rent Strokes: The Motion Picture."

The Horror Flick

Horror's subgenres are constantly evolving. In the past decade or so, we've gone from tongue-in-cheek horror with laughs à la "Scream" to surrealistic J-Horror like "The Ring" to the current fervor for "Hostel"-like movies rooted in the most disturbing imagery imaginable. This summer's leading contender for most-leaps-out-of-your-seat is "The Descent," a promising mixture of monsters and primal fear that could make "Snakes on a Plane" seem like charming traveling companions.

The Chick Flick

Okay, dude, she went with you to "X-Men," "Nacho Libre" and "The Fast and the Furious: Tokyo Drift." It's time for you to suck it up and take her to see "The Devil Wears Prada" or "The Lake House." Or maybe even both. Every summer there's gotta be a handful of movies strictly designed to appeal to the double-X chromosome set, if for no other reason than cosmic sexual balance.

The Remake

As if adapting comic books, TV shows and video games weren't lazy enough, Hollywood continues to propagate perhaps its most vilified tendency: to remake old movies (and rarely make them better). This year's "Poseidon" and "The Omen" both showed that improved effects technology and the passage of time is not enough of a reason to redo something that was perfectly fine as it was.

How Lowbrow Can You Go?

When it comes to comedies, you're unlikely to find cinematic fare by Wes Anderson or Charlie Kaufman during the sweltering months. More likely, the yuks will center around the pants area -- either flatulence in the back or smacks to the front. Lowbrow comedies like "Little Man" and "Clerks II" hold up the summer movie tenet of being anything but challenging.

The Clearasil Collection

It's an ever-increasing challenge: How to lure teenagers away from the home entertainment system and get 'em into the movie theaters. So Hollywood turns to the old standard: sex! Hormonally charged flicks like "John Tucker Must Die" shake some thong-flashin' booty in hopes of getting the teens off the Xbox for 90 minutes.

The Kids Meal

A genre that used to be the realm of low-budget, live-action Disney flicks that made about $750 at the box office has become one of Hollywood's biggest priorities: the kiddie flick. Kids' films today are usually CGI 'toons tied in to more merchandising than Bill Gates could afford. "Cars" leads the pack ahead of "Monster House" and "The Ant Bully" this summer.

The Exceptions to the Rule

Of course, not every movie during the middle months is a lowbrow stew of effects and fart jokes. More adult fare like "Little Miss Sunshine," "Wordplay," "A Scanner Darkly" and "The Science of Sleep" always manage to sneak their way in-between the blockbusters to give filmgoers some respite from the fluff.

And this is not to say that summertime is the sole domain of the mindless blockbuster. Those bad boys are perennials, they just work better this time of year. There's something about escaping the blazing heat of summer by downing a mountain of junk food in an arctic-chilled darkened theater with a friend while some truly silly entertainment unfolds in front of you. It's the perfect escape. And you rarely get stung by a jellyfish.

Check out everything we've got on "Miami Vice", "Little Miss Sunshine" and "Clerks II."

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