Hip hop stars Kid Cudi and Kanye West used to be cool, but not so much these days. Kid Cudi called West out in a series of tweets in September and West offered a scathing response during one of his concerts.
Singers Monica and Brandy reunited in 2012 for a new song, "It All Belongs To Me." Their original duet, 1998's "The Boy Is Mine" won them a Grammy. In September 2016 it was reported that the pair were on the outs.
Rapper Azealia Banks and Disney child star Skai Jackson got into a heated exchange on Twitter in May after Banks tweeted some derogatory remarks about singer Zayn Malik.
Fans were upset when Miley Cyrus posted some unflattering photos of "Full House" star Jodie Sweetin from her partying days. Sweetin took the high road, saying, "I don't pay attention to negative stuff."
Reality star Kim Kardashian didn't take too kindly to Bette Midler criticizing her for posting a nude selfie on Monday, March 7. Midler tweeted, "If Kim wants us to see a part of her we've never seen, she's gonna have to swallow the camera," and Kardashian responded by accusing the actress of trying to be a "fake friend."
Iggy Azalea, left, and Britney Spears were chummy at the Billboard Music Awards in May, but now they may be at odds over the lack of success of their single "Pretty Girls."
Playboy founder Hugh Hefner's former girlfriends Kendra Wilkinson-Baskett, left, and Holly Madison argued over Madison's portrayal of their former life at the Playboy Mansion in her new book.
Rappers Dwayne "Lil Wayne" Carter, left, and Bryan "Birdman" Williams were once the father and son of Cash Money Records. Now the pair are in a $51 million dollar court battle over Carter's contract and the delayed release of "Tha Carter V."
Mariah Carey and Nicki Minaj shared the judges' table during season 12 of "American Idol," and they bickered all season. "Let's just say I don't think they had any intentions for us to have a good experience doing that show," Carey reflected in a recent interview on Australian radio. "Pitting two females against each other wasn't cool."
Onetime friends Denise Richards and Heather Locklear hit a major impasse after the former started dating the latter's ex, Bon Jovi's Richie Sambora. In interviews, Richards denied that she and Locklear were still friends at the time she began seeing Sambora.
It's a case of he said/she said/he said. Eminem set it off after he claimed to have had a torrid dating relationship with singer Mariah Carey, who denied it. Her husband, Nick Cannon, even offered to defend her honor by meeting the rapper in the ring.
Oprah Winfrey was reportedly annoyed by David Letterman's constant joking references to her name when he hosted the Academy Awards in 1995. The late-night talk-show host told "The Daily Show's" Jon Stewart he had also once played a practical joke on Winfrey, convincing a waiter that she had agreed to pick up his tab. They have since made peace.
Tom Cruise got on Brooke Shields' bad side by decrying her use of medication to treat postpartum depression. Shields responded with an op-ed in The New York Times, and Cruise later apologized for his remarks.
Paris Hilton and Nicole Richie helped to coin the term "frenemies" after their very public bust-up in 2004. The former "Simple Life" co-stars went on to make up two years later.
It appears that rapper Lil' Kim has not taken too kindly to what she views as Nicki Minaj's lack of respect and similar style with the colored wigs and sexually explicit lyrics. The pair have traded insults all over the media.
Kanye West and Taylor Swift had one of the greatest celeb feuds of all time. The rapper famously grabbed the singer's mic at the 2009 MTV Video Music Awards. He later apologized, and she seemed to accept his apology via her song "Innocent."
Model Amber Rose served it up to reality Khloe Kardashian on Twitter after Kardashian criticized her for talking about Kardashian's younger sister Kylie Jenner during an interview. Let's just say the word "hoe" was used.
Abigail Breslin's big music debut did not go over well with fans of Australian boy band 5 Seconds of Summer. In a song called "You Suck," the actress sings about the wrongdoings of unnamed prior loves; judging from some of the lyrics, 5SOS fans inferred that Breslin was taking aim at 5SOS singer Michael Clifford. They retaliated with a series of mean tweets under the hashtag #AbigailYouTried.
Lorde is not the kind of girl to stand idly by while someone picks on her friends. When DJ/producer Diplo teased Taylor Swift about her backside, Lorde jumped in with a fiery comeback. If they wind up at a music show together, things may get awkward.
When Chris Brown learned what "The Real" co-hosts Adrienne Bailon and Tamar Braxton had to say about his relationship with Karrueche Tran, the singer defended his (then) girlfriend in a social media tirade. Among other things, Brown criticized Bailon as being an "ole trout mouth" and labeled Braxton as "Muppet Face."
Sharon Osbourne is also not a fan of U2's giveaway. The TV personality took the group and Bono to task in September 2014 for releasing a free album via iTunes. She called their music "mediocre" and the group "middle-age political groupies."
Kim Kardashian didn't mention actress Adrienne Bailon by name when she went on a Twitter rant last July, but it was pretty obvious whom she was speaking of. Bailon, who used to date Kim's brother Rob, spoke ill of the past relationship in a magazine interview. Kim then tweeted, "Funny how she says being with a Kardashian hurt her career yet the only reason she has this article is bc she is talking about a Kardashian ... So sad when people try to kick my brother when he is down #FamilyForever."
Freddie Prinze Jr. worked with Kiefer Sutherland on the Fox series "24" in 2010 and said his experience with the actor was so horrible, he wanted to quit acting. Yet while Prinze called Sutherland "the most unprofessional dude in the world," Sutherland responded via his rep that he enjoyed working with his former co-star.