The Stooges were commonly known by their first names: "Larry, Moe, and Curly" and "Moe, Larry, and Shemp," among other lineups. The act originally featured Moe Howard (born Harry [Moshe] Moses Horwitz in 1897), brother Shemp Howard (born [Shmuel] Samuel Horwitz^[1]), and longtime friend Larry Fine (born Louis [Levi] Feinberg). Shemp was later replaced by brother Curly Howard (born Jerome Lester [Yehudah-Leib] Horwitz) October 22, 1903. When Curly suffered a debilitating stroke in 1946, Shemp rejoined the act. After Shemp's death in 1955, he was replaced by bald-headed comedian Joe Besser, after the use of stuntman Joe Palma to record several "Shemp" shorts after his death. Eventually Joe "Curly-Joe" DeRita (born Joseph Wardell) would replace him. After Larry suffered a serious stroke in 1970 he was unable to continue performing. Emil Sitka, a longtime actor in Stooge comedies, was contracted to replace Larry—but no film was ever made with him in the role, although publicity photographs exist of him with his hair combed similarly to Larry's posing with Moe and Curly-Joe (see below). However, Larry's paralyzing stroke in 1970 effectively marked the end of the act. He died in January 1975. Moe died of cancer a few months later.

The Three Stooges started in 1925 as part of a raucous vaudeville act called 'Ted Healy and His Stooges' (a.k.a. 'Ted Healy and His Southern Gentlemen', 'Ted Healy and His Three Lost Souls' and 'Ted Healy and His Racketeers'—the moniker 'Three Stooges' was never used during their tenure with Healy). In the act, lead comedian Healy would attempt to sing or tell jokes while his noisy assistants would keep "interrupting" him. Healy would respond by verbally and physically abusing his stooges. Brothers Moe and Shemp were joined later that year by violinist-comedian Larry Fine, and Fred Sanborn joined the group as well.

The original Three Stooges in their film debut, Soup to Nuts. Many fans forget that Shemp Howard (far left) was the original third Stooge before his youngest brother Curly Howard assumed the role.

In 1930, Ted Healy and His Stooges, including Sanborn, appeared in their first Hollywood feature film: Soup to Nuts, released by Fox Studios. The film was not a success with the critics, but the Stooges' performances were considered the highlight and Fox offered the trio a contract without Healy. This upset Healy, who told studio executives that the Stooges were his employees. The offer was withdrawn, and after Howard, Fine and Howard learned of the reason, they left Healy to form their own act, which quickly took off with a tour of the theatre circuit. Healy attempted to stop the new act with legal action, claiming they were using his copyrighted material. There are accounts of Healy threatening to bomb theaters if Howard, Fine and Howard ever performed there, which worried Shemp so much that he almost left the act; reportedly, only a pay raise kept him on board. Healy tried to save his act by hiring replacement stooges, but they were not as well-received as their predecessors.^[2] In 1932, with Moe now acting as business manager, Healy reached a new agreement with his former Stooges, and they were booked in a production of Jacob J. Shubert's The Passing Show of 1932. During rehearsals, Healy received a more lucrative offer and found a loophole in his contract allowing him to leave the production.^[2] Shemp, fed up with Healy's abrasiveness,^[2] decided to quit the act and found work almost immediately, in Vitaphone movie comedies produced in Brooklyn, New York.

With Shemp gone, Healy and the two remaining stooges (Moe and Larry) needed a replacement, so Moe suggested his younger brother Jerry Howard. Healy reportedly took one look at Jerry, who had long chestnut red locks and a handlebar mustache, and remarked that he did not look like he was funny.^[2] Jerry left the room and returned a few moments later with his head shaved (though his mustache remained for a time), and then quipped "Boy, do I look curly." Healy liked the name, and thus 'Curly' was born even though his hair wasnt "curly". (There are varying accounts as to how the Curly character actually came about.)

In 1933, Metro Goldwyn Mayer (MGM) signed Healy and his Stooges to a movie contract. They appeared in feature films and short subjects, either together, individually, or with various combinations of actors. The trio was featured in a series of musical comedy shorts, beginning with Nertsery Rhymes. The short was one of a few shorts to be made with an early two-strip Technicolor process; the shorts themselves were built around recycled film footage of production numbers cut from MGM musicals, some of which had been filmed in Technicolor. Soon, additional shorts followed (sans the experimental Technicolor), including Beer and Pretzels, Plane Nuts, and The Big Idea.

Healy and company also appeared in several MGM feature films, such as Turn Back the Clock, Meet the Baron, Dancing Lady, Fugitive Lovers, and Hollywood Party. Healy and the Stooges also appeared together in Myrt and Marge for Universal Pictures. In 1934, the team's contract with MGM expired, and the Stooges parted professional company with Healy. According to Moe Howard in his autobiography,^[3] the Stooges split with Ted Healy in 1934 once and for all because of Healy's alcoholism and abrasiveness. Their final film with Healy was MGM's 1934 film, Hollywood Party.

Both Healy and the Stooges went on to separate success. Healy died under mysterious circumstances in 1937.

The same year, the trio (now christened The Three Stooges) signed on to appear in two-reel comedy short subjects for Columbia Pictures. In Moe's autobiography, he said they each got $600 per week on a one-year contract with a renewable option; in the Ted Okuda–Edward Watz book The Columbia Comedy Shorts, the Stooges are said to have gotten $1,000 between them for their first Columbia effort, Woman Haters, and then signed a term contract for $7,500 per film, to be divided among the trio. According to Moe, Columbia Pictures studio head Harry Cohn would always wait until the last minute to renew the contract.^[3] The Stooges, too worried about keeping their jobs in an increasingly declining short-subject market, would not dare ask for a raise during the 23 years they worked for Cohn. The Stooges appeared in 190 film shorts and five features under the "original" contract with Columbia. Del Lord directed more than three dozen Three Stooges shorts. Jules White directed dozens more, and his brother Jack White directed several under the pseudonym "Preston Black". (In the early shorts, Curly was billed as "Curley", and also as "Jerry Howard" when receiving a writing credit.)

The Stooges during their prime years with Curly on board. Promotional photo from the 1938 short Wee Wee Monsieur.

According to a published report,^[4] Moe, Larry, and director Jules White considered their best film to be You Nazty Spy!. This 18-minute short subject starring Moe as "Moe Hailstone", an Adolf Hitler-like character satirized the Nazis in a period when America was still neutral and isolationist about WWII. You Nazty Spy! was the first Hollywood film to spoof Hitler, released in January, 1940, nine months before Charlie Chaplin's The Great Dictator. Reportedly this film caused the Stooges to be placed on Hitler's so-called "death list" because of its anti-Nazi stance. Chaplin, along with Jack Benny, would also be on this list due to their later anti-Nazi films.

The Stooges made occasional guest appearances in feature films, though generally they stuck to short subjects. Columbia offered theater owners an entire program of two-reel comedies (15 to 25 titles annually) featuring such stars as Buster Keaton, Andy Clyde, Charley Chase and Hugh Herbert, but the Three Stooges shorts were the most popular of all.^[2]

Curly was easily the most popular member of the team.^[2] His childlike mannerisms and natural comedic charm made him a hit with audiences. The fact that Curly had to shave his head for the act led him to feel unappealing to women. To mask his insecurities, Curly excessively drank, ate and caroused whenever the Stooges made personal appearances, which was approximately seven months out of the year. His weight ballooned in the 1940s, and his blood pressure was dangerously high.^[5] His wild lifestyle and constant drinking eventually caught up with him in 1945, and his performances suffered. Anyone viewing Curly's last dozen shorts will see a seriously ill Curly, struggling to get through even the most basic scenes.^[2]

During the filming of Half-Wits Holiday on May 6, 1946, Curly suffered a debilitating stroke, and the film was finished without him. (He is absent from the last several minutes of the film.) Curly's health necessitated a temporary retirement from the act, and while the Stooges hoped for a full recovery, Curly never starred in a film again. He did make one brief cameo appearance in the third film after Shemp returned to the trio, Hold That Lion!. It was the only film that contained all four of the original Stooges (the three Howard brothers and Larry) on screen simultaneously; Jules White recalled Curly visiting the set one day, and White had him do this bit for fun. (Curly's cameo appearance was recycled in the 1953 remake Booty and the Beast.) ^[3] In 1949, Curly was supposed to play a cameo role in the Stooge comedy Malice in the Palace, but his chef role was played by Larry.

Moe Howard turned to his older brother Shemp Howard to take Curly's place. Shemp, however, was hesitant to rejoin the Stooges, as he had a successful solo career at the time of Curly's untimely illness. However, he realized that Moe's and Larry's careers would be finished without the Stooge act. Shemp wanted some kind of assurance that his rejoining was indeed temporary, and that he could leave the Stooges once Curly recovered. Unfortunately, Curly's condition declined until his death on January 18, 1952.

Shemp appeared with the Stooges in 73 more shorts and a quickie Western comedy feature titled Gold Raiders. During this period, Moe, Larry and Shemp made a pilot for a Three Stooges television show called Jerks of All Trades in 1949. The series was never picked up, although the pilot is currently in the public domain and is available on home video, as is an early television appearance from around the same time on a vaudeville-style comedy series, Camel Comedy Caravan, originally broadcast live on CBS-TV on March 11, 1950 and starring Ed Wynn. Also available commercially is a kinescope of Moe, Larry and Shemp's appearance on The Frank Sinatra Show, broadcast live over CBS-TV on January 1, 1952. Sinatra was reportedly a big fan of the Stooges and slapstick comedy in general. On this broadcast, the Stooges are joined by one of their longtime stock-company members Vernon Dent, who plays "Mr. Mortimer", a party-goer who requests a drink. The Stooges oblige with disastrous results.

The Three Stooges during the Shemp years (1947–1956), as represented in Malice in the Palace.

The quality of the Stooge shorts declined after Columbia's short-subject division downsized in 1952. Producer Hugh McCollum was discharged and director Edward Bernds resigned out of loyalty to McCollum, leaving only Jules White to both produce and direct the Stooges' remaining Columbia comedies.