LOS ANGELES — Johnny Carson once noted that his career as host of "The Tonight Show" had exceeded his most optimistic dreams.

"I could never have imagined," he said, "That I would walk through that curtain almost 5,000 times for 30 years."

The curtain fell on the final act of Carson's life yesterday, when TV's greatest entertainment legend died in his sleep at age 79, attended by family members. The cause was emphysema.

His passing was cloaked in as much discretion as all his private affairs. Although Carson had announced he was ill several years ago, his death came without a hint of advance news. No public memorial service will be held.

In a business where everyone's work is taped, it is elementary to say Carson's achievements survive him. His performance from 1962 to 1992 on "The Tonight Show Starring Johnny Carson" continues to surface in retrospectives and clips of surpassing comic brilliance.

But Carson's influence on the entire medium is just as eternal and more profound. He vaulted late-night TV into the modern form we know today, creating a staple that has endured while other fashions come and go.

GARY NULL / KNIGHT RIDDER NEWSPAPERS Comic Jay Leno appears as a guest with Johnny Carson on "The Tonight Show Starring Johnny Carson" on April 28, 1977. Leno took over for Carson in 1992.

Only last Tuesday, Peter Lassally, senior vice president of David Letterman's Worldwide Pants production company, told television critics in Los Angeles that Carson still sent jokes to Letterman and that it pleased him greatly when they were used.

Carson's up-to-the-minute interest in TV would surprise no one who knew him.

"If television was ever invented for somebody, it was for him," observed long-time sidekick Ed McMahon, who uttered the "Heeeeeere's Johnny!" that famously introduced Carson each night.

In fact, Carson and television came of age together, matching individual and industry evolution step for step. It would prove to be a partnership made in ratings heaven. By the 1980s, he was seen by 15 million viewers a night, according to The Washington Post.

Like TV, Carson's roots were in radio. Born Oct. 23, 1925, in Corning, Iowa, Carson was raised in Nebraska. After a stint in the Navy and four years of college, he worked at Nebraska stations before moving to the exciting new thing called television.

Despite good looks and an aptitude for mimicry that could have carried over into acting, Carson was a born comedian and prankster. He performed magic, ventriloquism and above all, loved to write and do humorous sketches.

He eventually moved west to Hollywood and starred in "Carson's Cellar," a low-budget local series that attracted the attention of comics Groucho Marx, Fred Allen and Red Skelton. He got a job as a writer on "The Red Skelton Show" in 1952.

In a sketch, Johnny Carson portrays fortuneteller Carnac the Magnificent.

His break came in rather dramatic fashion two years later when Skelton was knocked unconscious during rehearsal just an hour before the live program aired. Carson was rushed in as a substitute and made his first hit with a national audience.

Meanwhile, television itself was changing.

The loud, knock-em-dead style that characterized TV comedy in the early 1950s was giving way to a more intimate, underplayed approach that seemed better suited to people's living rooms.

The sitcom became more refined, and so did a new breed of variety host: a sort of show-biz news anchor who also could take part in the fun.

This development suited Carson perfectly. He was a cool guy, and as network executives were figuring out, television was a cool medium.

He secured his first big starring turn in "The Johnny Carson Show," a 1955 CBS sketch and singing show that did not last long. It was followed by a stretch on an ABC game show "Who Do You Trust," where luck struck again. Carson met and hired Ed McMahon as his announcer.

Despite the failings of the CBS and ABC programs, it seemed certain the immensely likeable Carson would get another shot at hosting.

That opportunity came in 1962, when Jack Paar — whose "Tonight" show tenure had been so successful, the program was renamed "The Jack Paar Show" — told NBC that he was tired of the job and leaving.

"Tonight" already had a tradition of laid-back, intelligent hosts. Before Paar was the owlish, intellectual comic, Steve Allen.

But soon after "The Tonight Show Starring Johnny Carson" debuted in 1962, the program began to assume a new look. First came a stand-up monologue by the host, then a series of interviews with guests punctuated by comic sketches involving host and guests.

Later came the big introduction, the Paul Anka-penned theme music and a ritualistic golf swing. Carson engineered a move from New York to what soon was known to millions as "beautiful downtown Burbank."

It all seems so simple today. Yet until Carson teamed with producer-director Fred De Cordova, no one had given such a definite shape to the late-night variety show.

Aided by other staples — McMahon as foil and a progression of affable bandleaders best exemplified by Doc Severinsen — "Tonight" took on the feel of a jovial club that invited viewers to kick back and relax.

At the center of the formula was Carson: polite, deadpan and possessed of an elusive personality that paradoxically came off as accessible to a wide range of fans. He was Midwestern, yet very polished — so much so, he sponsored a clothing line carried in hundreds of stores. He was well-read; his guest list regularly included authors, politicians and scientists. Yet, he was boyishly ready to pull off silly gags.

Among the silliest was his alter-ego Carnac the Magnificent, a mocking send-up of a soothsayer. In an era before irony dominated popular culture, Carson brandished the deliberate falsity of the act, sharing the con with viewers.

Other beloved creations included Aunt Blabby and hysterical patriot Floyd R. Turbo.

Carson's most renowned gift was his spontaneous wit and timing, tested frequently by a preference for guests and acts that eluded control.

Perhaps the most famous unplanned moment was when guest Ed Ames demonstrated his tomahawk-throwing technique. Aiming for the image of a cowboy on a prop wall, Ames' effort went awry, striking the paper cowboy target square in its crotch.

Audience and crew went into hysterics. It remained only for Carson to deliver the coup de grace. Just as the audience settled down, he looked at Ames and said, "I didn't even know you were Jewish."

Carson was a tireless worker and a perfectionist. He cut "Tonight" from 90 to 60 minutes when he thought there was not enough good material to sustain more than an hour. During his reign, the show won numerous Emmys.

Over the years, he appeared on numerous variety shows such as "Rowan and Martin's Laugh-In." He hosted the Academy Awards five times, displaying the kind of subtle, barbed delivery and easy presence that made him a worthy successor to Bob Hope.

Carson's professional warmth and generosity were equally famous. Like Ed Sullivan, he was a determined recruiter of new talent and he specialized in comedians. Those Carson helped early on included George Carlin, Bill Cosby, Joan Rivers, Roseanne Barr and Jerry Seinfeld.

Carson's off-screen life appeared less congenial. Three of his four marriages ended in divorces, and two were marked by acrimonious negotiations.

Happily, he seemed to find nuptial success with Alexis Maas, whom he married in 1987 and who survives him along with two sons from his first marriage, Chris and Cory. A third adult son, Richard, died in a car accident in 1991.

He also knew when to quit, an instinct bestowed on few stars since Greta Garbo.

At his retirement announcement in 1992, he hinted that he would be involved on the air in some future projects. But he disappeared from television soon after. One of his last performances was voice work for "The Simpsons" in the 1993 "Krusty gets Kancelled" episode.

Instead, he spent his retirement yachting — he was occasionally seen in Puget Sound and the San Juan Islands — traveling and socializing at his home in Malibu.

Carson eschewed attention behind the scenes, as well. Although he preferred Letterman to Jay Leno as the new "Tonight" host, he did not openly criticize NBC's decision.

Instead, his company proceeded to co-produce "Late Night with David Letterman" for CBS.

Certainly, Letterman is the current host who most embodies Carson's aptitude for goofy bits mixed with smart, sardonic humor. Some critics also see aspects of Carson in Jon Stewart of "The Daily Show."

When Carson went off the air May 22, 1992, "Tonight" was still No 1 in ratings (as it is now). His next-to-last program was marked by a sung tribute from Bette Midler, after which she and a visibly moved Carson fell into a duet of "Here's That Rainy Day."

Many viewers still fondly believe it was the final episode.

In the end, Carson's title as the King of Late-Night Television stands no matter who happens to occupy the host's chair. His legacy ranks with that of the early pioneers who invented the sitcom — an accomplishment unique to television.

"It's a marvelous, marvelous medium, and I'm optimistic about it," he said a few years ago, then characteristically added, "Of course, optimism in the television business is like an accordion player with a beeper."

Associated Press and CNN

contributed to this story.