Each weekday evening, the war that is late night television rages on in millions of American households. With an eye on the bottom line, networks scramble to win the ratings battle of the late night talk show.

Armed with topics ranging from politics to entertainment, David Letterman, Jay Leno, Bill Maher, Craig Kilborn and Conan O'Brien attempt to win over the public with witty humor and interesting guests.

David Letterman and Jay Leno continue to square off against each other with their respective late night offerings.

Airing at 11:30 p.m. on CBS, "The Late Show with David Letterman" offers a wide variety of quirky humor and self-deprecating antics. NBC's "The Tonight Show with Jay Leno" airs opposite Letterman and offers a more mainstream type of humor.

Leno's best points come not from his own humor but from the humor of real life. One of his best segments is his weekly display of real newspaper headlines that — due to typos and errors — read as truly hilarious jokes.

In another recurring segment, Leno interviews ordinary (or, as it seems, incredibly stupid) people about basic historical facts and current events. The ignorant responses people give are funnier than any scripted comment about the issue.

"The Tonight Show" fails, however, in its various skits and scripted sequences. These skits vary greatly in content but not in quality. They typically come off as forced and seem downright annoying and out of place.

Leno is unable to execute these skits effectively because he lacks the necessary delivery to make the silly seem brilliant.

Letterman, on the other hand, has mastered this skill. The sincerity in which he delivers his jokes makes the absurdity strike the balance between brilliance and stupidity.

Letterman's indifferent and seemingly impenetrable attitude on the show heightens the jokes to a new level of humor.

It is with this style that Letterman can pull off much more than Leno.

Letterman is the master of self-deprecation. Oftentimes, his show is best when things go horribly wrong. When a joke is clearly failing, he will turn it around with a sarcastic comment about how great the show is.

Letterman's segments are also generally better than Leno's. One particular segment is Letterman's "Know your current events."

This weekly studio audience quiz game has many variations, including "Know your cuts of meat," "Know your Janet Reno eyeglasses" and "Know your wedding announcements in last Sunday's New York Times."

While Leno's monologue is generally funnier than Letterman's, Leno cannot seem to transfer this stand-up comic attitude to the rest of the show, as Letterman has. Letterman seems to be able to inject comedy in even the most un-funniest of premises.

The Election 2000 showdown in Florida has highlighted this difference between the two comedians. Leno's monologue jokes have been quite funny and clever, while Lettermen's are simply mediocre.

However, Letterman seems to handle the issue much better in other forms. He recently placed a dozen American flags behind his desk to out show Bush and Gore and "act more presidential."

Letterman also compared two of the candidates' recent speeches, counting how many times they said "vote," "count," "president" and "people." Not only was this funny, but it was also revealing of the two candidates.

One clear distinction between the two hosts is in the way Leno and Letterman handle their guests. Instead of just plugging their latest movie, Letterman is able to make even the most mundane interview seem entertaining.

Letterman also is known for having memorable guests. On a recent show, Richard Simmons came out dressed as a turkey in bright colors. Letterman calmly responded by spraying Simmons with a fire extinguisher.

Leno, on the other hand, seems to handle his guests as just plugs for their current projects. Also, Leno seems to feature outdated celebrities.

On a recent show, Leno showcased the comedian Carrot Top. Some of Carrot Top's biggest jokes were a slew of — that's right — Clinton jokes. Letterman responded to this with a series of "Clinton Classics" that are delivered with such ironic undertone as to almost be mocking Leno's outdated guest.

Letterman is a unique host in another way. His band leader, Paul Schaffer, is the only talk-show band leader on television that is actually funny and relevant to the show. Letterman and Schaeffer are almost a team, as Schaffer plays an active role in many of the show's pieces.

Overall, Letterman seems to be more on top of his game. He has clear command of his format, being able to transfer his distinct comedy style to many different forms while not betraying its brilliant backbone.

As his monologue shows, Leno is the better stand-up comic, but he stills seems uncomfortable with the role he plays. He has never really fit it well, and it shows now more than ever.

Unfortunately, Letterman's deft mastering of the late night talk show format doesn't seem to rub off on the rest of CBS's late night lineup.

Following "The Late Show" on CBS is "The Late Late Show with Craig Kilborn." Kilborn, formerly of Comedy Central's "The Daily Show," has none of the qualities that make Letterman's show great.

When he was hosting "The Daily Show," Kilborn's self-absorbed pretty boy act played well against the quirky backdrop of a daily news satire. When given his own show, however, this focus on himself comes across as mere arrogance.

Kilborn continues to do a news segment that is similar to "The Daily Show," and it is now obvious that the success of that show is due to the writers. The same premise fails on Kilborn's show.

It is obvious that Kilborn is trying to gain audiences who enjoyed his previous work, but the content is neither inspired nor clever.

When Kilborn left "The Daily Show," he took the "Five Questions" segment with him. "Five Questions," in which the guest answers a range of questions from trivia to personal, is the only funny part of Kilborn's show. Kilborn must think it is amusing to act pompous and self-absorbed, but he lacks the ability to pull it off.

Airing locally at 1:30 a.m. on NBC, Conan O'Brien continues to shine as a bright spot on late night television.

After losing partner Andy Richter over the summer, many believed there would be a downturn in the quality of "Late Night with Conan O'Brien." However, O'Brien seems more comfortable than ever flying solo in the late night chair.

Like Letterman, Conan appears confidant in his ability. He has control of his format, and this allows him to flex his comedic muscles. He has one of the funniest monologues on television, still showing his ability as a stand-up comic without succumbing to trite and forced jokes.

Conan O'Brien has been well-known for his recurring segments from the Pimpbot to Triumph, the Insult Comic Dog. One of the best features is a segment called "If They Mated," in which two celebrity photographs are combined to form a possible image of their theoretical offspring.

Breaking away from the talk show format is "Politically Incorrect with Bill Maher," airing after Ted Koppel's "Nightline"on ABC.

Bill Maher's show is a combination of a political round table and a late night show.

Each night, Maher brings together a new group of four people ranging from serious political analysts, comedians, singers and actors to a multitude of other people from areas such as politics or the press.

While many of the recent shows have understandably focused too much on the recent presidential election debacle, this show tends to focus on a variety of current issues facing the nation.

"Politically Incorrect" is fascinating not only for its occasional humor, but because people from completely different backgrounds clash on many issues.

The show is a fascinating study on opposing views regarding all types of subjects.

Everything is discussed on the show, and oftentimes there isn't nearly enough time to satisfy the viewer.

The show's format allows everyone to have an opinion, without making judgment calls on the validity of the opinion.

At times, however, comedian guests can get in the way. While Maher can deliver jokes at opportune times without hampering serious debate, many of his guests feel a need to wisecrack about everything. Their comments are rarely funny and mainly disruptive, tending to break up the flow of the evening's debate.

Aside from "Politically Incorrect," late night television offers the same basic format: a talk show with comedians hosting. This format is what drives the various styles of Letterman, Leno, Kilborn, and O'Brien.

The differences between the late night hosts lay in how they handle that format, and the control and confidence they show. Being funny helps, too.

The views expressed here are those of the author and not necessarily those of The Observer.

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