Originally there were three Cunningham children. The eldest, Chuck, was phased out of the show (supposedly, he went off to college on a basketball scholarship), because according to Garry Marshall, "we realized that Fonzie was really the 'big brother' character the show needed". In the final episode, Howard comments that he's proud of his "two kids".
Fonzie's full name is Arthur Herbert Fonzarelli.
The only person Fonzie allowed to call him by his proper name (Arthur) was Mrs. Cunningham.
Arthur "Fonzie" Fonzarelli's character was originally to be named Arthur Maschiarelli (creator Garry Marshall's real last name) and nicknamed "Mash." When ABC first picked up the show, they had Marshall change the character's name because they felt that "Mash" might remind people of "M*A*S*H' (1972)', a popular show on a rival network.
When the show first started it centered primarily on Ritchie and Potsie (as did the "Love American Style" episode of which "Happy Days" as based). Fonzie would make appearances (usually helping them out of trouble); as would Ralph, who was sort of a jerk character (neither Henry Winkler or Don Most appeared in the beginning credits of season one). In seasons to come, Ralph would become good friends with Richie and Potsie (equal with Potsie), and Fonzie's character would step up to be equal - and then later to overshadow - Ritchie's character.
It's a common belief that George Lucas' American Graffiti (1973) was the inspiration for this series. In actuality, the pilot for the series (seen on "Love, American Style" (1969)) aired before Lucas began production on his film. However, the success of that movie caused producer Garry Marshall to reconsider his failed pilot and turn it into a series.
Among the differences between the show's beginnings as the "Love and the Happy Day" episode on "Love, American Style" (1969) and its premiere two years later as a series is that the role of Howard Cunningham originally was played by Harold Gould instead of Tom Bosley and there was no Fonzie on that episode.
Bill Haley and the Comets' classic "Rock Around The Clock" served as the theme song for the first season of the show. For the first series episode the original 1955 recording was used, but for the remaining shows' opening credits of season one the band recorded a special version of their famous song.
The more familiar "Happy Days" theme was used in the opening credits beginning with the 1975-1976 season. An entirely new arrangement of the theme was introduced during the 1983-1984 season.
ABC at first feared Fonzie would be perceived as a hoodlum or criminal, and prohibited his wearing a leather jacket. In the first few episodes Henry Winkler wears an incredibly non-threatening gray windbreaker. Fortunately the network saw the light and an icon was born.
In the first season, The Fonz wore a blue windbreaker. Starting in season two, he wore his trademark brown leather jacket, which now hangs in the Smithsonian.
The Fonz became so popular that after the first few seasons the network wanted to rename the show "Fonzie's Happy Days" or just "Fonzie." Threatened resignations by Garry Marshall and Ron Howard ended this idea.
For its first season and most of its second season, the series was shot in single camera format. The familiar Cunningham living room set made its debut in the 1975-1976 season, and was used for the rest of the series run. It is a rearrangement of the original Cunningham living room used in the first and second seasons.
Originally started out being filmed with a laugh track and a single camera. Three episodes from the 1974-1975 season were later filmed before a studio audience with three cameras as an experiment. Beginning with the 1975-1976 season, the series switched full time to the three-camera, live studio audience format. The long familiar living room set arrangement used throughout most of the series' run made its debut at the beginning of the 1975-1976 season.
Many fans agree that the show's quality deteriorated after the three-part-season 5 opener, "Hollywood", where Fonzie jumps a shark while water-skiing. Today, when a show takes a sharp drop in quality, it's said to "jump the shark".
Robby Benson and Don Most were both considered for the role of Richie Cunningham. The character of Ralph Malph was created for Most.
Joanie Cunningham's middle name was Louise.
Comedian Phil Silvers once did a cameo in an episode as Jenny Piccalo's dad. Jenny Piccalo was played by his real-life daughter, Cathy Silvers.
Fonzie always referred to Joanie Cunningham as "Shortcake".
Lynda Goodfriend appeared earlier on the show as Ralph's girlfriend before taking on the role as Richie's girlfriend (and later wife) Lori-Beth.
Linda Purl originally played the recurring role of Richie's girlfriend Gloria in the first season before she took the later role of Fonzie's girlfriend Ashley.
During his first appearance, Mork is looking at television and the show he is looking at is "The Andy Griffith Show" (1960), which featured Ron Howard. He even makes a comment to that he really liked the show especially Opie, who was played by Howard.
In the final episode, Tom Bosley stepped out of character and turned to the camera thanking the viewers for being part of the Cunningham family for the many years the show had been on.
In one episode the Cunninghams are coming out of a theater playing The Music Man (1962) when Mrs. Cunningham comments that the little boy in the movie looks just like Richie (Ron Howard) when he was little. Mr. Cunningham replies that she's being silly and that the boy in the film looks nothing like Richie. In fact, Howard did indeed play the little boy, Winthrop Paroo, in the film, when he was eight years old.
Anson Williams' voice was the one heard when songs like "Hound Dog" were playing on the juke box.
Henry Winkler has said that he based some of Fonzie's movements and speech pattern on Sylvester Stallone. Winkler had worked with Stallone years earlier in The Lord's of Flatbush (1974). Winkler vowed when he played Fonzie, he would never comb his hair on camera or have a pack of cigarettes rolled up in his T-shirt sleeve and he never did.
Originally Fonzie had a younger cousin named Spike who would show up occasionally during the first few seasons. He was written out after the third season.
When Ron Howard and Don Most left the show, their absences were explained by having Richie and Ralph join the army.
Chachi's real name was Charles.
Pinky and her TV sister Leather's name Tuscadero was taken from the real-life town of Atascadero, in California. Leather was played by singer/bass guitarist Suzi Quatro, who'd achieved pop stardom in England and wanted to bring her career back to America.
Richie Cunningham's favorite song is "Blueberry Hill" by Fats Domino.
Its ratings were so low at the end of its first season that it came close to being cancelled. Then Henry Winkler's "Fonzie" character started to catch on with viewers, the ratings took a turn for the better, and the show wound up running ten years.
Marion's maiden name was Kelp.
Ron Howard at first passed on playing Richie, because he didn't want to "be a teenager the rest of my life" on television. He reconsidered when Garry Marshall promised him if the series were picked up, Richie and his friends would graduate high school and become adults. Even Fonzie went back to night school, to graduate with the gang.
It was originally intended that Potsie would be Richie's best friend, showing him the ropes of young adulthood. The viewer response to Fonzie was so strong, though, that the writers' focus shifted, and Fonzie took Potsie's place.
Marion was an archaeology major in college.
The name of the garage that Fonzie worked in was Bronko's.
The character 'Howard Cunningham' was ranked #9 in TV Guide's list of the "50 Greatest TV Dads of All Time" (20 June 2004 issue).
The name of Leather's backing group was the Suedes.
Potsie's father, who was often talked about but never seen, owned a gas station.
The house used for the exterior shots of the "Cunningham" home in the opening sequence, as well as various points throughout the show's run, is located at 565 N Cahuenga Blvd, Los Angeles, CA 90004.
Pat Morita's character is called Arnold, but in one episode he reveals that the restaurant was named Arnold's when he bought it, and he couldn't afford to replace the sign. His real name is Mitsumo Takahashi.
Ron Howard admitted that the reason he left the USC Film School before graduating is because he was cast in this series.
In the first episode of the series, "Arnold's" was identified as "Arthur's" (different name on the logo, but with the same rotating, stylized letter "A" above the name). The restaurant and teen hangout became "Arnold's" as of the second episode.
The show's line "Sit on it!" was ranked #8 in TV Guide's list of "TV's 20 Top Catchphrases" (21-27 August 2005 issue).
After the show became successful, Garry Marshall was approached and asked if the show could do anything that would help convince kids to read. In one episode, the Fonz realized that he would go to the library and check out a book, despite his reputation. (Said the Fonz, "Everybody is allowed to read.") That week, registration for library cards went up 500 percent.
At the height of the show's popularity, a call came through to Paramount Studios, from a teen-aged boy who was contemplating suicide, and "wanted to talk to Fonzie". Henry Winkler took the call, and gave the boy a pep-talk about life, convincing him to give it another chance.
Among the merchandising produced during the show's run were T-shirts (proclaiming "Sit on it!"), a line of figures from Mego (featuring a Fonzie whose thumbs could be posed up or down), and a record compilation of 1950s hits, whose cover was a souvenir photo of Henry Winkler in character. (A disclaimer read "No! The Fonz has not taken to singing on this album!")
In the first few episodes with Fonzie, he could only wear his leather jacket if he was on or near his motorcycle. The producers felt it would tone down the hoodlum image since it would appear he was wearing it for safety reasons.
Chachi's trademark saying, "Wa Wa Wa", came from Scott Baio always saying "What What What".
During the character's short run on the series, older brother Chuck Cunningham would usually be holding a basketball.
Ralph Malph's trademark line was (after telling a joke): "I still got it!"
Happy Days was so popular that "Rock Around the Clock" went back on the pop charts 19 years after its original release. The song was #1 in 1955, and made it to #39 in 1974.
In summer of 1976, "Theme From Happy Days" was a hit single, peaking at #5 on the national charts.
Fonzie has a picture of the Lone Ranger in his wallet.
Crystal Bernard first appeared as a one episode character named Mikki in the 9th season before returning as Howard's niece K.C. Cunningham the following year.
Tom Hanks guest starred late in the series as an old rival of Fonzie's who had learned martial arts and wanted to settle the score in a fight.
Linda Purl's contract was not renewed for the show's final season. Consequently her absence was explained by having Ashley return to her estranged husband to try to patch up their marriage.
"Potsie" got his name because he loved to work with clay as a kid (he was especially fond of having made a big clay ashtray).
Howard Cunningham drove a De Soto for most of the series. He finally traded it for a red 1962 Studebaker Lark.
A bronze statue of the Fonz was unveiled in Milwaukee, Wisconsin on August 19, 2008. The statue is located along the Milwaukee River riverwalk, at the south end of the Rock Bottom Brewery's outdoor seating area. Actors Henry Winkler, Marion Ross, Tom Bosley, Erin Moran, Don Most, Anson Williams, Penny Marshall, and Cindy Williams attended, as did director/producer Garry Marshall and producer Robert L. Boyett. The event included an autograph signing with proceeds to benefit the Boys & Girls Club Literacy Program, a performance by Joey Sorge, the Fonz in the "Happy Days" stage musical, a parade of stars down Wisconsin Avenue, and a ceremony at the Brewers Miller Park in which the cast threw out the first pitch and Anson Williams sang the national anthem.
Although Fonzie loved motorcycles, Henry Winkler was terrified of them. Most of the scenes of Fonzie riding the motorcycle were shot with the bike attached to a platform, and being pulled by a truck.
The house used for the exterior shots of the "Cunningham" home in the opening sequence, as well as various points throughout the show's run looked nothing like the interior of the set. For one, the garage was to the right of the front door but the set had a window where the garage should be, the garage was located next to the kitchen door which meant the garage's driveway wasn't in front of the house at all. Fonzie lived over the garage and there was a set of stairs that led up to his apartment