Trivia: Born on a Belgian army base, curly brown-haired Johnny Galecki grew up in Chicago and started acting professionally at the age of 12. He made his feature film debut in 1988 as River Phoenix's little brother in A Night in the Life of Jimmy Reardon. He then assumed the role of Rusty Griswold in National Lampoon's Christmas Vacation, and gained his first regular role on a TV series as Robert Ulrich's son in American Dreamer. In 1991, he starred in the made-for-TV movie Backfield in Motion, co-starring the production team of Roseanne and Tom Arnold. The next year, Galecki joined the cast of Roseanne as Darlene's sensitive and put-upon boyfriend David Healy. He stayed on the show until its final season in 1997, although he wasn't on very much during its last few years. His other television credits include several guest appearances, leading roles in made-for-TV movies, and a part on the short-lived Head of the Class spin-off Billy. After Roseanne ended, he got back into features with small parts in I Know What You Did Last Summer, Bean, and Suicide Kings. He continued playing slightly effeminate sensitive males in The Opposite of Sex and Morgan's Ferry. After bit parts in Bounce, Playing Mona Lisa, and Vanilla Sky, Galecki played a leading role in the comedy thriller Bookies, which premiered at the 2003 Sundance Film Festival. In 2007 he landed the leading role in the sitcom The Big Bang Theory and it grew to be one of the most popular shows on TV, earning Galecki Emmy, Golden Globe, and Sag nominations in 2011 for his work on the show. He maintained his movie career in projects such as Hancock and In Time.

Trivia: Kaley Cuoco began modeling and acting at the tender age of six, when she was cast in the TV movie Quicksand: No Escape. Growing up in front of the camera, the young actress continued to appear as the requisite little girl in movies like Virtuosity and Picture Perfect until she was cast as teenage daughter Bridget on the sitcom 8 Simple Rules. TV would prove to be the actor's bread and butter, and she would go on to star on Charmed, 6Teen, and Monster Allergy, not to mention The Big Bang Theory, a show that earned her legions of fans as Penny, the hot neighbor of two geeky physicists (Johnny Galecki, Jim Parsons). Cuoco also continued to appear in films, though on a much smaller scale compared to her TV work. She appeared in a supporting role in the Easter film Hop in 2011, and played the female lead opposite Kevin Hart and Josh Gad in The Wedding Ringer in 2015.

Trivia: Though initially typecast in comedic roles -- including a small turn in Old School (2003), a contribution to Tracey Ullman in The Trailer Tales (2003), and work on MADtv -- American character actor Simon Helberg quickly branched out into diverse genres. He appeared as a CBS page in George Clooney's revered Edward R. Murrow biopic Good Night, and Good Luck., as a junior agent in Christopher Guest's For Your Consideration (2006), and in a recurring role on the Aaron Sorkin comedy drama Studio 60 on the Sunset Strip. In 2007, Helberg was cast in the regular role of Howard Wolowitz on the sitcom The Big Bang Theory, about a couple of nerdy physicists (Johnny Galecki and Jim Parsons) who struggle with women, and everything else outside the lab. In 2007, Helberg also made appearances in the comedies Mama's Boy and Walk Hard: The Dewey Cox Story. He played a young rabbi in the Coen brothers film A Serious Man (2009), and continued to make guest appearances on TV shows such as Kick Buttowski: Suburban Daredevil and Drunk History, while maintaining his regular status on The Big Bang Theory.

Trivia: Actor Kunal Nayyar first made a splash in Hollywood playing physicist Koothrappali on the series The Big Bang Theory, which debuted on CBS in 2007. In 2012 Nayyar voiced the character of Gupta in Ice Age: Continental Drift, and the following year he could be seen opposite Gina Gershon and Billy Campbell in the thriller, The Scribbler. In addition to his feature work Nayyar also co-wrote the critically acclaimed play Cotton Candy, which runs in New Delhi.

Trivia: Name means "water" in Hebrew. Had her big break in the 1988 film Beaches, playing the younger version of Bette Midler. Appeared in the music video for Michael Jackson's "Liberian Girl." Made her television debut in the 1980s fantasy series Beauty and the Beast. Best known for her role as the title character in the sitcom Blossom. Was successful in many voiceover roles in animated series, including Kim Possible and Hey Arnold! Appeared on a 2009 episode of What Not To Wear. Her The Big Bang Theory character, Amy Farrah Fowler, is a neurobiologist, corresponding to Bialik's real-life degrees in neuroscience. Is a spokesperson for the Holistic Moms Network and gave birth to her second son at home.

Trivia: Began her career as a comedian and had a one-woman show, The Miss Education of Jenna Bush, in which she played the daughter of former president George W. Bush. Co-wrote, directed and starred in the comedic short The Condom Killer. Toured with the political-satire group Gross National Product. Performs with The Realest Real Housewives show, in which comedians read transcripts from the Real Housewives franchise. Was a recurring guest star on series 3 of The Big Bang Theory before joining the cast as a series regular in series 4.

Trivia: After graduating from Yale drama school in 1988, bookish actor Joshua Malina was cast in Aaron Sorkin's Broadway production of A Few Good Men and began a collaboration that would span decades. Malina had his first film role in the 1993 Hollywood adaptation of Sorkin's play and also appeared in the Sorkin-penned romantic drama The American President. A few small roles followed -- notably a part in 1998's Bulworth and a multiple-episode stint on HBO's The Larry Sanders Show -- before Sorkin came calling again in 1998, casting Malina as one of the leads in the critically acclaimed ensemble show Sports Night.Despite awards and a loyal cult-following, Sports Night was canceled after only two seasons. Meanwhile, another Sorkin-produced prime-time drama quickly became a hit with both critics and audiences. Though Malina wasn't part of the cast of The West Wing when it premiered in 1999, he joined up in 2002 to fill the void left by the departing Rob Lowe. Malina remained with The West Wing throughout its run, which ended in 2006, but wasted no time before landing another TV gig. In 2007, he was cast alongside former Alias star Michael Vartan in the ABC corporate drama Big Shots. After a five-year hiatus from the big and small screens, he took a small part in Jonathan Kasdan's The First Time.

Trivia: Kal Penn qualifies as one of the very few Indian-American actors of Gujarati heritage working in Hollywood. He was born Kalpen Suresh Modi on April 23, 1977, in Montclair, NJ, to an engineer father and a mother employed as a fragrance sampler for a perfume manufacturer. Modi bravely and intelligently cut against the grain of social expectations as a child, rejecting the prompting of his peers to join the soccer team, and instead joining the school drama team. Though allegedly mocked by classmates for his decision, Penn changed everyone's mind with his performance in a school production of The Wiz, and received a standing ovation for his work in that production -- no mean accomplishment for a beginner. During elementary school and junior high, Modi felt struck, again and again, by the crass Indian stereotypes perpetuated in Hollywood films, specifically in movies such as Indiana Jones and the Temple of Doom (1984) and 1986's Short Circuit, in which Caucasian actor Fisher Stevens plays the Indian-American Ben Jabituya for comic relief. Quietly vowing to work against this trend, Modi actually spent years attaining the box-office clout to make it happen. After his secondary school education (first at New Jersey's Howell High, then at Freehold Township High), Modi trained intensely as a dramatist on the Manhattan theatrical circuit, then attended UCLA as a drama major in the mid-'90s, and simultaneously started to land television parts right and left, in such series as Buffy the Vampire Slayer, Sabrina, the Teenage Witch, and Spin City. At about that time, he took the advice of friends and family, and -- though initially reluctant to do so -- anglicized his name, changing it to Kal Penn. As a result, he later reported, job offers escalated by 50 percent.Penn made his feature debut coming in the 1999 culture-clash drama Freshmen. A supporting role in the independent romantic comedy American Desi (2001) quickly followed -- ironically, an exploration of race and identity, about an Indian-American boy, Krishna (Deep Katdare), who moves away from home and changes his name to Kris to disguise his ethnicity, but finds himself saddled with several roommates of like heritage. Penn plays Ajay, an Indian student who has immersed himself in black ("Afrocentric") behavior. The film received extremely limited U.S. theatrical bookings in the spring of 2001 and fair reviews from the critics who saw it. Penn then jointed the cast of the Animal House-cloned gross-out farce National Lampoon's Van Wilder (2002), about a seventh-year senior (Ryan Reynolds) threatened by his father's (Tim Matheson) decision to cut off his seemingly unlimited allowance. Widely drubbed as unfunny, the picture did embarrassing box office and opened and closed in one month, but its A-list issue nonetheless gave Penn (who plays Van's Indian friend, Taj Mahal Badalandabad) with his highest-profile exposure to date. Penn's onscreen activity escalated meteorically from 2003 through 2006, with the young actor averaging around seven or eight first-run features per year, and ascending to higher and higher credit billings. Most notably, he co-starred as Kumar (alongside fellow Gen-Xer John Cho) in 2004's stoner comedy Harold and Kumar Go to White Castle, a surprise sleeper hit (and recipient of many enthusiastic notices) about two buddies, an Asian-American banker and an Indian-American medical student, whose unstoppable quest to find some White Castle hamburgers gives way to an epic road trip. Penn also delivered a brief supporting turn as Stanford, a henchman of Lex Luthor (Kevin Spacey) in 2006's Superman Returns. Meanwhile, Penn made an indelible impression on the small screen as well, as Harrison in the 2004 NBC 9/11 NBC drama Homeland Security. Penn was less effective in the ill-advised 2006 sequel National Lampoon's Van Wilder: The Rise of Taj, an installment that -- per its title -- finds Penn's Taj Mahal Badalandabad carrying Van's off-the-wall hijinks to Camden University in England. Penn subsequently signed on for an additional sequel, 2007's Harold & Kumar Escape from Guantanamo Bay, which finds the boys of the title mistaken for terrorists when they attempt to slip a bong aboard a flight to Amsterdam. That same year, Penn would headline Epic Movie, a massively scaled attempt to "send up" the Hollywood fantasy epic, Airplane! style,and join the cast of Fox's hit series thriller 24, during its sixth season. A Very Harold and Kumar Christmas followed in 2011, with concurrent roles in television's How I Met Your Mother and House guaranteeing continued small screen exposure between big screen outings.

Trivia: Sean Astin had starred in ten movies, directed a short film, and formed his own production company all before his 21st birthday. The elder son of actress Patty Duke and actor/director John Astin, he knew the hazards of Hollywood life: As a popular child star, Astin refrained from drinking, drugs, and narcissism. He juggled acting with attending classes at Crossroads High School for the Arts and Los Angeles Valley College, eventually graduating cum laude from the University of California at Los Angeles with dual degrees in History and American Literature and Culture. When his younger brother, fellow kid actor Mackenzie Astin, temporarily fled Los Angeles to pursue journalism, Astin doggedly remained in town -- he once half-heartedly considered a law career, but could never part with being an entertainer. Astin was born in Santa Monica, CA, on February 25, 1971. His famous parents actively supported his childhood ambition to become an actor, and Astin was cast in TV specials, movies, and even series until 1983. Barely a year later, screenwriter Steven Spielberg handpicked the 13-year-old Astin to star as Michael "Mikey" Walsh in Richard Donner's children's adventure film The Goonies (1985). Astin earned his first Young Artist Award for his work on the film and went on to act in a host of teen pictures. He headlined the Disney Channel television movie The B.R.A.T. Patrol (1986), joined Kevin Bacon for the wilderness adventure White Water Summer (1987), and appeared with Dudley Moore and Kirk Cameron in the comedy Like Father, Like Son (1987).In 1988, Astin directed his first short film, a Vietnam picture about the unexpected relationship between an American GI and a Viet Cong soldier titled On My Honor. Astin's own production company, Lava Entertainment, financed the film. While continuing to develop projects through Lava Entertainment, Astin starred with Dermot Mulroney in 1989's Staying Together. He won his second Young Artist Award for his performance in the picture. Also in 1989, Astin portrayed the teenage son of feuding couple Kathleen Turner and Michael Douglas in Danny DeVito's The War of the Roses. He finished off the '80s by enlisting in the all-star cast of Michael Caton-Jones' World War II drama Memphis Belle (1990). The film -- which also features Matthew Modine, Harry Connick Jr., Billy Zane, and Eric Stoltz -- followed the crew of the Memphis Belle bomber on their harrowing final run over Germany. Astin's stocky build and comic timing lent well to his incarnation as the group's tail gunner, Sergeant Richard "Rascal" Moore. When Astin initially lost the lead role in his next picture, Toy Soldiers (1991), to Wil Wheaton, he treated the film's director, Dan Petrie Jr., to a screening of Memphis Belle. Petrie was so impressed by his work that he relegated Wheaton to a supporting part and cast Astin as Toy Soldiers' hero, a rebellious student who saves his prep school from South American terrorists.In the spring of 1992, Astin starred with Pauly Shore and Brendan Fraser in Encino Man, a comedy about two California high school students who discover a caveman. He then reunited with Dermot Mulroney in the drama Where the Day Takes You (1992), which also stars Will Smith, Christian Slater, Lara Flynn Boyle, and Ricki Lake. 1993 saw Astin play the title character in Rudy, the memorable film about a tenacious boy determined to play football for Notre Dame despite the fact that he is too small. Football coaches around the United States still show the film before games to inspire their players, and, to this day, strangers still chant "Rudy! Rudy!" when they spot Astin on the street.After filming Safe Passage (1994) with Susan Sarandon and Sam Shepard, Astin appeared in the independent film The Low Life (1995), for which he won the Best Actor Award at the 1995 Fort Lauderdale Film Festival. That same year, he wrote, directed, and produced his second short film, Kangaroo Court. The picture tells the story of a police officer who is put on trial by an inner-city gang and stars Gregory Hines and Michael O'Keefe. It earned Astin an Academy Award nomination for Best Short Film (coincidently, John Astin was nominated in the same category for his film Prelude in 1969).Astin continued to work steadily throughout the '90s. In 1995, he starred in Showtime's adaptation of Kurt Vonnegut Jr.'s futuristic short story Harrison Bergeron. In 1996, he made a cameo as a doomed soldier in the first feature film to depict Desert Storm, Edward Zwick's Courage Under Fire. In 1997, he directed and starred in an episode of HBO's Perversions of Science called "Snap Ending" and was one of several narrators in the Academy Award-winning Holocaust documentary The Long Way Home. In 1998, Astin took a small role in Warren Beatty's Bulworth and began work on a string of independent films -- including Boy Meets Girl (1998), Dish Dogs (1998), Kimberly (1999), Deterrence (1999), and Icebreaker (1999). The decade also brought changes to Astin's personal life. On July 11, 1992, he married Christine Astin (born Harrell) at Patty Duke's Idaho farm. The couple met when she worked at Astin's talent agency and they co-founded Lava Entertainment together. Then, in 1994, Astin underwent DNA testing that revealed rock promoter Michael Tell to be his biological father (Patty Duke and Tell had been briefly married before her engagement to John Astin). Though the actor is friendly with Tell, he still considers those who raised him to be his parents. Two years later, Astin and his wife had their first child, Alexandra Louise, in November of 1996. In the summer of 1999, Astin landed the coveted part of portly hobbit Samwise "Sam" Gamgee in Peter Jackson's highly anticipated three-film adaptation of J.R.R. Tolkien's The Lord of the Rings trilogy. Auditions for the role were held over several months in every English-speaking country in the world. Astin's father had appeared in Jackson's horror film The Frighteners, and the veteran actor's fondness for the director made Astin determined to get the part. When he found that his only competition was an overweight English thespian, Astin gained 30 pounds to secure the role. All three installments of the trilogy -- The Fellowship of the Ring (2001), The Two Towers (2002), and The Return of the King (2003) -- were filmed simultaneously over an 18-month period in New Zealand. Astin's wife and daughter accompanied him to the shoot and Alexandra made her acting debut as a young hobbit in Sam Gamgee's family. The couple had a second child, Elizabeth Louise, between the release of the first and second films.After the success of the Lord of the Rings franchise, Astin kept busy with a slew of projects throughout the 2000s, like 50 First Dates, Click, and an arc on the TV series 24. Astin would also do extensive voice acting in the 2000s and 2010s, on kids shows like Special Agent Oso and Teenage Mutant Ninja Turtles.