His career spanned the famous Bakersfield sound, the outlaw era, and 38 No. 1 hits on the country music charts. Now comes word that Merle Haggard has died Wednesday — his 79th birthday.

Haggard gave voice to people living hard-scrabble lives, and it was a voice he came by honestly. Born in 1937 in Oildale, Calif., just outside Bakersfield, he grew up living in a converted boxcar and spent his early years bouncing between jails and oil fields, and playing music in bars.

Here are five things to remember about the man who was often called the poet of the common man:

"Incorrigible": This is the word people say Haggard's mother used when she dropped her son off at a juvenile detention center — when he was 11 years old. By that time, he had already started hopping onto freight trains.

And as recently as 2010, Haggard used the word to describe himself, saying in an interview on NPR's Fresh Air: "I was probably the most incorrigible child you could ever meet. I was already on the way to prison before I realized it, actually. I was really kind of a screw-up."

Cash And Lefty: It's often noted that when Johnny Cash performed "Folsom Prison Blues" at San Quentin Prison in 1958, Haggard was in the audience, as an inmate — and that the experience prodded him along in his own career. But to Haggard, a bigger idol was Lefty Frizzell, whose craftsmanship left a huge impression on Haggard at least as early as his teenage years.

Haggard is quoted writing in the forward of Frizzell's biography, "The impact Lefty had on country music is not even measurable. ... No one could handle a song like Lefty. He would hold on to each word until he finally decided to drop it and pick up the next one. Most of us learned to sing listening to him."

The Outlaw: For much of his career, Haggard operated outside of the Nashville system that generated smooth — some would say too-smooth — country music. Instead, he used a rougher honky-tonk sound as the backdrop for songs that turned the problems of ordinary people into works of art.

His musical talent is credited with saving Haggard from a life of run-ins with the law, and it certainly helped him clear his record: in 1972, California's then-Gov. Ronald Reagan, granted him a full pardon for his previous crimes.

The Songs: Haggard became known as a supremely talented songwriter, and his songs such as "Mama Tried," "Okie From Muskogee," "Today I Started Loving You Again" and "Sing Me Back Home" have been covered by other artists countless times.

His music also easily translated into rock — "Honky Tonk Night Time Man" was famously recorded by Lynyrd Skynyrd, for instance. And "Mama Tried" was recorded by both the Grateful Dead and the Everly Brothers.

Legacy: Haggard never stopped making music, and although he often complained about life on the road, he was doing his best to tour in recent months, as he fought off serious health problems (including, in December, pneumonia).

Even back in 2009, Haggard's longevity was already being noticed by Will Oldham, an acclaimed songwriter who has called Haggard one of his idols.

"He's writing and singing better than he ever has," Oldham told The New Yorker. "And it's just like, well, there's no excuse, then. You can't just say that it goes away, or that the music industry kills it, or whatever."

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