Tevin Campbell
Introduced to the music world by super-producer Quincy Jones in 1990, Tevin Campbell earned his first No. 1 R&B/Hip-Hop single at just 13-years old with his guest turn on Jones' "Tomorrow (A Better You, Better Me)." That same year, he appeared in Prince's "Graffiti Bridge" film, armed with a No. 3 hit single "Round and Round." For the next four years, he continued to regularly chart top 10 hits and No. 1s with "Tell Me What You Want Me To Do," "Alone With You" and "Can We Talk."
En Vogue
En Vogue is arguably the act that brought "girl groups" back to the top of the charts in the early 1990s, with a total of six No. 1 singles on the R&B/Hip-Hop Songs tally between 1990 and 1997. The quartet's first album, "Born To Sing," launched four top three hit singles, with three of them hitting No. 1 ("Hold On," "Lies" and "You Don't Have to Worry"). They returned with "Funky Divas" in 1992 with two more No. 1s in "My Lovin' (You're Never Gonna Get It)" and "Giving Him Something He Can Feel." Their most recent chart-topper came with "Don't Let Go (Love)" from the film "Set It Off" in 1997.
Smooth soul singer Joseph Thomas has placed 34 titles on R&B/Hip-Hop Songs, dating to his 1993 arrival with the No. 10-peaking "I'm in Luv," the first of his nine top 10s. Two of those tracks reached the summit: Mariah Carey's "Thank God I Found You," on which he guested with 98 Degrees (two weeks at No. 1, 2000) and his own "Stutter," featuring Mystikal (five weeks, 2001). Joe has twice reigned on R&B/Hip-Hop Albums, with "My Name Is Joe" (2000) and "Ain't Nothing Like Me" (2007).
The singer/actress wasted no time back in 1994 when, as a then 15-year-old, she took the R&B/Hip-Hop charts by storm with her debut single "I Wanna Be Down." It spent four weeks at No. 1 on the Songs chart, her first of nine top 10 singles. She reached the pinnacle again with her dueling-diva duet "The Boy Is Mine" with Monica in 1998. Brandy released four studio albums between 1994 and 2004 before taking a break until 2008's "Human." The latter set spawned her most recent hits: a pair of top 40 singles in the form of "Right Here (Departed)" and "Long Distance."
Kanye West
Kanye West came to prominence thanks to his work behind the scenes as a producer for Jay-Z's Roc-A-Fella Records in 2000. Jay's 2001 "Blueprint" set boasted West's work and soon he embarked on his own proper career as an artist. His breakthrough success on the charts came with his single "Through the Wire" (recorded literally through his wired-shut jaw following a near-fatal car accident), reached No. 8 on R&B/Hip-Hop Songs in 2004. Since, West has posted another 10 top 10 tracks on the list as well as taking all four of his album releases to No. 1 on R&B/Hip-Hop Albums.
Chris Brown
Chris Brown exploded onto R&B/Hip-Hop Songs at 16 years old with the chart-topping "Run It!" in 2005, going on to post 11 more top 10 singles on the list through 2008. After the singles from his 2009 album "Graffiti" failed to find the top 10 (the same year he pled guilty to assaulting his then-girlfriend Rihanna), he returned to the region when his mixtape single "Deuces" hit No. 1 in September of 2010. On R&B/Hip-Hop Albums, the singer has picked up two No. 1 albums with his self-titled debut in 2005 and "Graffiti." His second set, "Exclusive," topped out at No. 2 in 2007.
Neo-soul singer Gerald Maxwell Rivera enjoyed a string of R&B/Hip-Hop Songs hits between 1996 and 2001, including "Ascension (Don't Ever Wonder)" (No. 8) and "Fortunate" (eight weeks at No. 1). After an eight-year hiatus - "I didn't intentionally step away from all of it, but I just wanted to ... live my life a little bit, and then be able to make music with that pure experience again," he explained - Maxwell returned last year with the album "BLACKsummers'night," which became his second No. 1 on R&B/Hip-Hop Albums and included the 14-week No. 1 single, "Pretty Wings."

Patti LaBelle
Making music for more than 50 years, the legendary singer first scored chart success with the group the Blue-Belles, which eventually morphed into LaBelle in 1971. As a solo artist, LaBelle has placed 26 titles on R&B/Hip-Hop Songs and 17 on R&B/Hip-Hop Albums over the past 25 years. She led the former list for four weeks in 1986 with the Michael McDonald duet "On My Own" and has since tallied chart entries with Mary J. Blige, Mary Mary and Kanye West.
Destiny's Child
Few female vocal acts can boast about their individual members' successes like Destiny's Child, which launched the solo chart careers of Beyonce, Kelly Rowland, Michelle Williams and LeToya Luckett. As a group (whether in its early hitmaking quartet configuration, or later as a blockbuster trio), they were inescapable on our R&B/Hip-Hop Albums and Songs charts. All told, the children of destiny have so far etched 11 top 10 singles (including four No. 1s) and four top 10 albums (with three of them topping out at No. 1).
The singer first reached R&B/Hip-Hop Songs in 2004 as a writer (and, under his birth name, Shaffer Chimere Smith), having co-authored Mario's 11-week No. 1, "Let Me Love You." Ne-Yo has since co-penned No. 1s for stars including Beyonce ("Irreplaceable"), Rihanna ("Take a Bow") and Jennifer Hudson ("Spotlight"). His artist resume is likewise sparkling: three No. 1s on R&B/Hip-Hop Albums and 33 appearances on R&B/Hip-Hop Songs, including the No. 1s "Miss Independent" and Keri Hilson's "Knock You Down," on which he and Kanye West appear as featured vocalists.

Musiq Soulchild
Musiq Soulchild has posted eight top 10 tracks on R&B/Hip-Hop Songs since arriving with "Just Friends (Sunny)" in 2000 (No. 6). The Philadelphia singer, known for his soul and funk edge has packed a punch on the R&B/Hip-Hop Albums chart, where he has posted three No. 1 sets: 2002's "JusListen," 2007's "LuvAnMusiq," and 2008's "OnMyRadio." which spawned his top 10 singles on the R&B/Hip-Hop Songs chart, "IfULeave" and "SoBeautiful."
St. Louis-bred Nelly has become a hip-hop powerhouse since his debut single "(Hot S**t) Country Grammar" reached No. 5 on the R&B/Hip-Hop Songs chart back in 2000. His debut album "Country Grammar" spent six weeks atop R&B/Hip-Hop Albums in 2000 as well, the longest run at No. 1 that year. 2002's "Nellyville" and 2004's "Suit" are his other No. 1 albums. Back on R&B/Hip-Hop Songs, Nelly has posted 11 top 10 titles with four chart-toppers, including the now-classic "Hot In Herre," which spent six weeks atop the list in 2002, and the Kelly Rowland-assisted "Dilemma" which earned nine weeks that year as well.
Since 1999, the year his groundbreaking "Slim Shady LP" debuted, only Jay-Z (10), R. Kelly (8), and Lil Wayne (7) have posted more No. 1s on the R&B/Hip-Hop Albums chart than Eminem's six. Em's only set to not reach the top of the list was 2005's compilation "Curtain Call: The Hits" which still reached No. 2. The Detroit emcee has not been as successful on the R&B/Hip-Hop Songs chart, with his featured spot on Drake's "Forever" netting him his best showing at No. 2 in 2009. However, his 2010 album "Recovery" has earned 2010's so-far longest run at the summit of R&B/Hip-Hop Albums with 13 weeks.
Snoop Dogg
Calvin Broadus, better known as Snoop Dogg, is a hip-hop icon with a hitmaking career stretching back to 1992. His first chart appearance came courtesy of his featured turn on Dr. Dre's "Deep Cover," which peaked at No. 46 on R&B/Hip-Hop Songs in 1992, and was followed by his debut single "What's My Name?" reaching No. 8 the following year. His debut album "Doggystyle" opened at No. 1 on R&B/Hip-Hop Albums in December of 1993 and picked up five weeks at the top. Snoop followed it with three more chart-topping albums from 1996-1999. 2001's "Tha Last Meal" was his last set to reach the penthouse.
Bobby Brown
Brown blasted onto the Billboard charts as a member of New Edition, who enjoyed three No. 1s on R&B/Hip-Hop Songs before his departure from the act in 1985. He similarly reigned with the first single from his solo debut, "King of Stage," as "Girlfriend" topped R&B/Hip-Hop Songs in 1986. Brown added leaders from his breakthrough second set "Don't Be Cruel" in 1988-89 (the title cut, "My Prerogative" and "Every Little Step"); from "Ghostbusters II" in 1989 ("On Our Own"); and, from "Bobby" in 1992 ("Humpin' Around"). 

Tony Toni Tone
If you turned on your favorite R&B radio station anytime between 1988 and 1994, the chances of hearing a cut by Tony Toni Tone were pretty high. In those years, of the 14 singles that they charted on the R&B/Hip-Hop Songs chart, only three of them missed the top 10. Among their biggest hits were five No. 1 singles (four of them consecutive): "Little Walter" (1988), "The Blues" (1990), "Feels Good" (1990), "It Never Rains (In Southern California)" (1990) and "Whatever You Want" (1991).
The smooth sounds of the group Sade (led by vocalist Sade Adu) have been haunting the Billboard charts since their debut in 1984 with the single "Hang On To Your Love." Since then, the act has earned eight top 10 hits, including their most recent, "Soldier of Love." It was the title track from their 2010 album -- its first new studio effort in nearly 10 years. "Soldier" was the group's first No. 1 R&B/Hip-Hop Album since "Promise" reigned for 11 frames in 1986. On the R&B/Hip-Hop Songs tally, Sade's (so far) lone No. 1 came with "Promise" in 1988.
Kenny "Babyface" Edmonds
Producer/songwriter/artist extraordinaire Kenny "Babyface" Edmonds not only made a mark for himself as the go-to guy for tender ballads in the '90s, but also as an artist in his own right. As a performer, he's reached No. 1 on the R&B/Hip-Hop Songs chart twice with "It's No Crime" in 1989 and its follow-up, "Tender Lover." All told, he's racked up 14 top 10s, most recently with 2001's "There She Goes." On the R&B/Hip-Hop Albums chart, he's tallied five top 10s, including "Tender Lover," which reigned for 11 weeks back in 1989. His last release, 2007's "Playlist," was his third top 10 in a row, as it debuted and peaked at No. 7.
Gerald Levert
The singer packed quite a career into a life cut all-too short at age 40 in 2006. Having sang in the trios Levert and LSG (the latter a supergroup with Keith Sweat and New Edition's Johnny Gill) Levert charted 32 solo hits on R&B/Hip-Hop Songs between 1988 and 2007. His most recent top 40 single, "Can It Stay" hit No. 25 in 2010. The track, recorded in 2003, appears on "The Best of Gerald Levert," which debuted at No. 12 on R&B/Hip-Hop Albums.
The group in which the late R&B stuperstar Gerald Levert first showcased his voice and earned chart success also included his brother Sean Levert and friend Marc Gordon. All six of the act's entries on R&B/Hip-Hop Albums reached the top 10, between 1986 and 1997, and 12 of its 22 visits to R&B/Hip-Hop Songs culminated in No. 1 finishes. LeVert logged five No. 1s on the R&B singles chart, including its biggest Hot 100 crossover hit (No. 5), "Casanova," in 1987. Sadly, Sean Levert passed away at 39, two years after Gerald in 2008. The group continues as a duo of Gordon and Blaq Rose.
The harmony-heavy quartet created its moniker from the names of its pairs of brothers: JoJo and K-Ci Hailey and Donald and Dalvin DeGrate. Between 1991 and 1996, the act was a force on R&B/Hip-Hop Songs, sending 10 titles into the top 10, five of which reached No. 1. The group's first three albums reached the top of R&B/Hip-Hop Albums. Between 1993 and 2006, K-Ci and JoJo added 14 chart singles, including the No. 1 "All My Life," also a Hot 100 leader.
Keyshia Cole
Oakland-born Keyshia Cole broke into the R&B/Hip-Hop Albums chart in 2005 with her debut "The Way It Is" peaking at No. 2 and racking up 84 weeks on the list, the longest in her career. That album spawned a remarkable five singles, including the heart-wrenching smash "Love," which made it to No. 3 on the R&B/Hip-Hop Songs chart in 2006. Keyshia went on to release "Just Like You" in 2007 and "A Different Me" in 2009 which spent two and six weeks atop R&B/Hip-Hop Albums, respectively. The latter set produced her biggest single yet, "Heaven Sent," which spent nine weeks at the summit of R&B/Hip-Hop Songs in 2008.
50 Cent
Curtis "50 Cent" Jackson first appeared on the R&B/Hip-Hop Songs chart with his comical hit "How To Rob," featuring the Madd Rapper, peaking at No. 62 in 1999. After his now-infamous shooting in 2000, 50 returned to the chart in 2002 with "Wanksta" (No. 4) and broke through to the masses with "In Da Club" spending nine weeks atop the chart in 2003. The two tracks set up his first major label release "Get Rich Or Die Tryin'" which resided in the penthouse of R&B/Hip-Hop Albums for eight weeks (the longest run at No. 1 year) and has sold eight million copies to date, according to Nielsen SoundScan.
The late Aaliyah truly made her mark on Billboard's R&B/Hip-Hop charts before tragically dying in a plane crash on Aug. 25, 2001. In her short lifetime, she tallied up big hits with her debut single "Back & Forth" (No. 1 for three weeks in 1994), "At Your Best (You Are Love)" (No. 2 in 1994) and "If Your Girl Only Knew" (No. 1 in 1996). Yet, even following her passing, she continued to live on via the charts. Since then, she reached the top 10 five more times, with "Rock the Boat" (No. 2), "More Than a Woman" (No. 7), "I Care 4 U" (No. 3), "Miss You" (No. 1 for three weeks) and "Come Over" (No. 9).
Stevie Wonder
Though the legendary Stevie Wonder notched a stellar string of hit singles on the R&B/Hip-Hop Songs chart in the '60s and '70s, he continued to perform strongly on into the '80s and beyond with such No. 1s like "Part Time Lover" and "Skeletons." While he has reached the top 10 since 1992 on the Songs chart, he's had a relatively recent success on the R&B/Hip-Hop Albums chart, where "A Time To Love" debuted and peaked at No. 2 in 2005. Though his rate of releasing new material has slowed in recent years ("Love" was his first new album in a decade), a new Wonder release is always an event.
The trio of Tionne "T-Boz" Watkins, Lisa "Left Eye" Lopes, and Rozonda "Chilli" Thomas scored nine top 10s on R&B/Hip-Hop Songs during the '90s, including three No. 1s and the No. 4-peaking 1995 pop culture smash "Waterfalls." Tragically, Lopes was killed in a car accident in 2002. Her posthumous album "Eye Legacy" reached No. 44 on R&B/Hip-Hop Albums last year. The set combined Lopes' vocals with new studio contributions from acts including Bobby Valentino, Boyz II Men's Wanya Morris and her fellow TLC members, as well as Missy Elliott, on "Let's Just Do It."
Singer/actress Monica Arnold blasted onto R&B/Hip-Hop Songs at age 14 in 1995 with the No. 1 "Don't Take It Personal (Just One of Dem Days)" and returned to the summit the following year with "Before You Walk Out of My Life"/"Like This and Like That." She has since added four more toppers, including "The Boy Is Mine," with Brandy, in 1998 and "Everything to Me" earlier this year, the latter of which made Monica the first artist to crown the chart in the '90s, '00s and '10s. Two weeks after "Everything to Me" completed its seven-week reign, Monica earned perhaps the trendiest of homages: "
New Edition
Before N*Sync and New Kids on the Block, there was New Edition. Originally consisting of Bobby Brown, Ricky Bell, Michael Bivins, Ronnie DeVoe and Ralph Tresvant, the quintet harmonized their way to No. 1 hits such as 1985's "Mr. Telephone Man" before Brown struck out on his own in 1986. While the act was reduced to a quartet, they still enjoyed a string of top 10 hits on Hot R&B/Hip-Hop Songs until Johnny Gill joined the group in 1988. With Gill, New Edition landed its first No. 1 since 1985 with 1989's "Can You Stand the Rain.".
Anita Baker
Everyone was "Caught Up In the Rapture" of the sounds of Anita Baker back in 1986, when her second album, "Rapture," spent three weeks atop R&B/Hip-Hop Albums and spawned four top 10 hits on R&B/Hip-Hop songs. She then came back even stronger with her third set, "Giving You The Best That I Got," notching eight weeks atop the Albums list and netting two No. 1 singles with the title track and "Just Because." She most recently graced the Album chart with her 2005 holiday effort "Christmas Fantasy," peaking at No. 31.
Lil Wayne
Dwayne "Lil Wayne" Carter is the youngest artist on this list, at a mere 28 years old. His career began with Cash Money Records at the age of nine and by age 15, he had already debuted on R&B/Hip-Hop Albums with "Get It How You Live!!" as part of the Hot Boys (the album peaked at No. 37 in 1997). The New Orleans rapper's first solo release, "Tha Block Is Hot" opened atop the chart in 1999, the first of his seven No. 1 albums.  Wayne released his breakthrough album "Tha Carter III" with over a million copies sold in its first week.
After arriving at No. 27 on R&B/Hip-Hop Albums with "I'm Serious" in 2001, T.I. was dropped from Arista Records and rebounded by forming his own label, Grand Hustle Entertainment. His Grand Hustle debut "Trap Muzik" peaked at No. 2 on the list in 2003 and was followed by the chart-topping "Urban Legend" in 2004, "King" in 2006, "T.I. vs. T.I.P." in 2007, and 2008's "Paper Trail," which spent a career-best five weeks in the penthouse. His musical successes have unfortunately been clouded by legal trouble in recent years.
Fallen rapper Tupac Shakur is truly a hip-hop icon. Before his tragic death in September 1996, Pac had only released four albums, two of which reached the summit of R&B/Hip-Hop Albums -- 1995's "Me Against The World" (4 weeks) and 1996's "All Eyez On Me" (3 weeks). A short two months after his passing, "The Don Killuminati: The 7 Day Theory" was released under the pseudonym Makaveli and racked up six weeks atop the list through 1997. 2Pac seemed to eerily predict his tragic end on "Killuminati" and he certainly prepared for it.
Toni Braxton
Toni Braxton, who earned a No. 1 R&B/Hip-Hop Album in 2010 with her latest release, "Pulse," has been turning out hits since she arrived on the scene in 1992 with the single "Give U My Heart" (from the film "Boomerang"). That hit, which climbed to No. 2 on R&B/Hip-Hop Songs, was the first of 11 consecutive top 10 singles for the husky-voiced diva. She reached No. 1 with both "You're Making Me High/Let It Flow" and "He Wasn't Man Enough."
Boyz II Men
The group showed its range of talents from the start, arriving in 1991 with the new jack swing of "Motownphilly," a No. 4 R&B/Hip-Hop Songs hit, and following with the a capella harmonies of "It's So Hard to Say Goodbye to Yesterday," the latter of which became the first of the group's five No. 1s on the survey. Boyz II Men additionally inked three No. 1s on R&B/Hip-Hop Albums between 1991 and 1997, fueling the act's coronation in 1999 as Billboard's top group of the '90s.
LL Cool J
As one of the first signees to Def Jam Recordings in the mid-80's, James Todd Smith is indeed a hip-hop pioneer. His first release "Radio" reached No. 6 on R&B/Hip-Hop Albums in 1986 and follow-up "Bigger & Deffer" spent 11 weeks at the pinnacle in 1987, the third longest run at the top for a rapper, behind MC Hammer's "Please Hammer Don't Hurt (29 weeks in 1990) and Eminem's "Recovery" (13 weeks this year). The rapper-turned-actor has also starred in various television shows and movies including his 1995-1999 sitcom.
After enjoying success as part of Destiny's Child, which tallied three No. 1s on R&B/Hip-Hop Songs in 1998-2000, Beyonce has roared to solo superstardom, so far earning an even loftier five leaders, including such smashes as "Irreplaceable" (nine weeks) and "Single Ladies (Put a Ring on It)" (12 weeks), and No. 1s on R&B/Hip-Hop Albums with each of her three studio sets. Despite her chart domination and high-profile celebrity status, Beyonce is not even the highest ranked member of her own household on this list. Her rapper/husband Jay-Z claims bragging rights ahead.
Rapper/actor Christopher Bridges began his entertainment career as WHTA-FM/Atlanta's on-air personality Chris Lova Lova and with his charisma and lyrical ability, transitioned smoothly into recording as his first charting single "What's Your Fantasy" peaked at No. 10 on R&B/Hip-Hop Songs in 2000. His first official album "Back For The First Time" peaked at No. 2 on R&B/Hip-Hop Albums in 2000 and was followed four consecutive No. 1 releases, including 2003's "Chicken-N-Beer" which spawned his first No. 1 single as a lead artist "Stand Up" (five weeks).
Michael Jackson
The King of Pop might as well be called the King of R&B as well, considering his seven No. 1 R&B/Hip-Hop Albums (five of those in the past 25 years) and incredible string of hit singles. Though he's no longer with us, his music continues to live on -- both on record and on our charts. In 2009, he notched a No. 18 R&B/Hip-Hop Songs hit with the title track from his concert documentary film "This Is It," while the film's companion album also topped the R&B/Hip-Hop Albums tally.
Keith Sweat
Depending on your year of birth, maybe your favorite Keith Sweat song is 1988's "I Want Her," his first R&B/Hip-Hop Songs entry, and first No. 1; or, the 1991 slow jam "I'll Give All My Love to You"; or, 1998's "Come and Get With Me," featuring Snoop Dogg. The format stalwart has placed 30 titles on the chart through 2010, including 16 top 10s and seven No. 1s. Sweat's first five releases reached No. 1 on R&B/Hip-Hop Albums between 1988 and 1996. He added a sixth leader, "Just Me," in 2008.
Though the Purple One's chart history stretches back to 1978, when he arrived on R&B/Hip-Hop Songs with "Soft and Wet," he continued to reign on into the next four decades with seemingly endless singles and albums. Since 1985 (the start year for this countdown), he's racked up 30 entries on R&B/Hip-Hop Albums -- more than any other artist -- with 19 of them reaching the top 10. Most recently, his last three studio releases all debuted at No. 1: 2006's "3121," 2007's "Planet Earth" and 2009's "Lotus Flow3r/MPLSound/Elixr."
Alicia Keys
Alicia Keys exploded onto R&B/Hip-Hop Songs in 2001 with her anthem "Fallin' " spending four weeks atop the chart and has never looked back. Every one of her five albums has reached the summit of R&B/Hip-Hop Albums, including her latest, "The Element of Freedom," which opened 2010 with five weeks at the top. The classically-trained pianist-turned-singer has sold a staggering 17.1 million albums in the U.S., according to Nielsen SoundScan, in her nine-year history, making her No. 10 ranking on this list well-deserved.
Freddie Jackson
Pop fans may not be overly familiar with Freddie Jackson's hit singles (as he's never reached the top 10 on the Billboard Hot 100) but he was a core hitmaking act on our R&B charts between 1985 and 1999, with a string of 18 top 10 hits starting with the No. 1 "Rock Me Tonight" in 1985 up through 1992's No. 2 hit "I Could Use a Little Love (Right Now)." He landed four straight No. 1s, including a 26-week reign with 1986's "Just Like the First Time" -- the third-longest run at No. 1 in the history of the chart. Only MC Hammer's "Please Hammer Don't Hurt 'Em"  and Michael Jackson's "Thriller"  were bigger.
Shawn "Jay-Z" Carter has come a long way from having to form his own record label, along with Damon Dash and Kareem "Biggs" Burke, in 1996 to release to his music after being rejected by label after label. After his critically acclaimed debut "Reasonable Doubt" peaked at No. 3 on R&B/Hip-Hop Albums and sophomore release "In My Lifetime, Vol. 1" capped out at No. 2, his breakthrough album "Vol. 2 - Hard Knock Life" spent six weeks atop the list in 1998. Overall, the Brooklyn emcee has posted a record 11 No. 1 albums (including two shared with R. Kelly) and on R&B/Hip-Hop Songs.
Luther Vandross
The silky-voiced singer placed 36 hits on the R&B/Hip-Hop Songs chart, including 20 top 10s and six No. 1s, between 1985 and 2007. Sadly, his last two appearances followed his passing in 2005 at age 54. Key to Vandross' staying power was his ability to connect with younger audiences, courtesy of duets with Janet Jackson and Mariah Carey in the '90s and Beyonce in 2004. Before he suffered a debilitating stroke in 2003, he recorded "Dance With My Father,". The touching ballad won the 2004 song of the year Grammy Award and Vandross' album of the same name became his first to top the Billboard 200.
Since arriving modestly on R&B/Hip-Hop Songs with the No. 56-peaking "Call Me a Mack" (from the movie "Poetic Justice," starring Janet Jackson) in 1993, and on R&B/Hip-Hop Albums a year later with his self-titled debut set, which peaked at No. 25, Usher has gone on to sell 22.1 million albums, according to Nielsen SoundScan. Among his more recent non-chart-related credits: discovering Justin Bieber and being named one of Glamour's "50 Sexiest Men of 2010." (The mentor may have taught his protege a little too well: Usher placed at No. 38 on the list. Bieber ranked No. 7).
Janet Jackson
With a staggering 15 No. 1 singles on R&B/Hip-Hop Songs, Janet Jackson owns the most toppers on the tally in the past 25 years. Only R. Kelly and Usher, with 11 each, come close to the diva in that span of time. (Even Jackson's superstar older brother Michael trails, with just eight in that span of time.) Between the years of 1985 and 2001, Janet Jackson was an unstoppable force on the charts, landing more top 10s than any other act: 27. Going further, from 1985 through 2004, Jackson amassed 33 consecutive top 40 hits, beginning with the No. 40-peaking "Fast Girls" through the No. 18 hit "I Want You."
Mariah Carey
Having celebrated 20 years of conquering Billboard charts in 2010, Carey counts numerous records among her achievements. In addition to 10 No. 1s on R&B/Hip-Hop Songs and five on R&B/Hip-Hop Albums, her 18 Hot 100 No. 1s are the most among solo acts (and second only to the Beatles' 20) and "One Sweet Day," with Boyz II Men, remains the chart's longest-reigning No. 1 (16 weeks, 1995-96). With 52.7 million albums sold, according to Nielsen SoundScan, Carey stands as the best-selling R&B album artist (and third overall after Garth Brooks and the Beatles) since SoundScan began tracking sales in 1991.
Whitney Houston
When Whitney Houston arrived on the R&B/Hip-Hop Songs chart in 1984 as the featured guest star on Teddy Pendergrass' No. 5 hit "Hold Me," many knew that chart success was in her future. After all, it was in her genes: mother Cissy Houston was a respected gospel/R&B singer  and cousin Dionne Warwick had been a staple on the Billboard charts for decades. But no one could have expected just how big Houston would become. The diva not only went on to earn eight No. 1 singles on the R&B/Hip-Hop Songs chart, but also landed five No. 1s on R&B/Hip-Hop Albums, including her most recent, 2009's "I Look To You."
Mary J. Blige
The Queen of hip-hop soul was the title bestowed upon Mary J. Blige by Sean "Diddy" Combs who worked her debut album "What's The 411?" as an A&R exec at Uptown Records in 1992. On its way to spending seven weeks at the summit of Top R&B/Hip-Hop Albums, No. 1 singles "You Remind Me" and "Real Love" set the stage for Blige's illustrious career as one of the genre's most celebrated artists. She has since posted 20 top 10 tracks on R&B/Hip-Hop Songs, including "Be Without You," which spent a record-setting 15 weeks atop the list, and eight chart-topping albums.
R. Kelly
R. Kelly crowns our list of the top 25 R&B/hip-hop artists of the past 25 years with good reason. Since January of 1985, he's amassed 35 top 10 hits on R&B/Hip-Hop Songs (the most of any act in the time frame) and a total of 84 charting singles. Among those are 11 No. 1s, including "Bump N' Grind" (12 weeks at the top) and "Down Low (Nobody Has To Know)" (seven weeks) with Ronald Isley. Further cementing Kelly's hitmaker status is his staggering 11 No. 1s on R&B/Hip-Hop Albums. The R&B icon continued to post new chart achievements in 2010, as he notched his 56th top 40 single with "When a Woman Loves."
The tally was based on actual performance on Billboards weekly Hot R&B/Hip-Hop Songs and Top R&B/Hip-Hop Albums charts from Jan. 5, 1985, issue to the charts of date. Artists are ranked based on an inverse point system (which just means that who ever spent the most weeks at No. 1 earned greater value than those that spent most time at the lower end of the chart).  Our list includes recent chart-toppers as well as classic favorites, platinum-selling crossover divas and quiet-storm crooners, innovators you'd expect to see and some surprising inclusions you never saw coming. But each artist is an essential voice in a genre that has become the driving force in today's popular music. Now dissect the list, tear it apart, put it back together, and share your thoughts by clicking on the "contact us" tab.