"Hard to Explain" is the first single from New York garage rock band The Strokes (their only previously released material was "The Modern Age" EP).
 It was released first in the UK and was later released in the US with different album artwork.
 (The UK version has a photo of two chairs, one red and one black, facing the camera.
 The chairs appear to be in a diner or restaurant of some sort.)
 Because this single is the first from their debut LP "Is This It", "Hard to Explain" made the anticipation for the album proper very high, and when "Is This It" did come out it was widely hailed as one of the best of the year.
 The B-side of this single, "New York City Cops" was omitted from the US version of the album in the wake of the September 11 attacks on the World Trade Center (the chorus to the song contains the lines "New York City cops/They ain't too smart").
"Knock You Down" is a song by American singer and songwriter Keri Hilson, recorded for her debut studio album "In a Perfect World..." (2009).
 The song features guest vocals from Ne-Yo and Kanye West.
 All three artists co-wrote the song with its producer Nate "Danja" Hills, as well as Kevin Cossom and Marcella Araica.
 The song was released first released to rhythmic and urban airplay in the United States as the album's fourth single in the US, and it would later serve as the third worldwide single.
The Atlanta International Documentary Film Festival (also called DocuFest Atlanta, Atlanta DocuFest, and DocuFest) is a film festival that screens documentary films in Atlanta, Georgia, United States.
 Paul Mariano's "Also Ran" was named Best Political Documentary at the 2006 festival.
 Don Wilson's "Mississippi Son: A Filmmaker's Journey Home" was named Best Dramatic Documentary at the 2007 festival.
 In 2009, Roger Nygard's "The Nature of Existence" was screened at the festival, as was Mike Ramsdell's "The Anatomy of Hate: A Dialogue for Hope", which won the Audience Choice Award that year.
 LGBT documentary film "It Doesn’t Define Us" was screened at the 2010 festival. "
The Cartel", a documentary about state schools in New Jersey, won the festival's Audience Choice Award that year.
 At the 2012 festival, Christine Anthony's and Owen Masterson's "Grow!"
 won the Audience Choice Award.
 "Decadence: Decline of the Western World" was named that year's Best Foreign Documentary.
Single Video Theory is a music documentary directed by Mark Pellington that follows the making of "Yield", the fifth album by the American alternative rock band Pearl Jam.
 It was released first on VHS on August 4, 1998, and then on DVD on November 24, 1998.
Guylaine Maroist is a Canadian journalist, filmmaker, musician, scriptwriter and film director.
 She is well known for her documentary productions such as "Gentilly or Not To Be", "Time Bombs", "The Disunited States of Canada", and "God Save Justin Trudeau".
 In 2011 she received the Governor General’s History Award for Popular History (The Pierre Berton Award) for her TV documentary series "J’ai la mémoire qui tourne" ("My Memories On a Roll").
 She is President of Productions de la Ruelle, a documentary film production company in Montreal, and President of Les Artistes pour la Paix, a Quebec NGO advocating peace and nuclear disarmament.
What Remains of Us (original title: Ce qu'il reste de nous) is a 2004 Canadian documentary film exploring the survival of the nonviolent resistance movement in Tibet.
 The documentary was shot over eight years without the knowledge of the Chinese authorities.
"S.O.S. (Let the Music Play)" is a song performed by American R&B and pop recording artist Jordin Sparks.
 It is the second single from her second studio album titled, "Battlefield".
 The song was released first in New Zealand on August 14, 2009 and was sent to US radio on September 29, 2009.
 It was released in the United Kingdom on October 12, 2009.
Juliet Weber is a producer, director, writer, and an editor for the film industry.
 She co-produced films such as Fastpitch (2000) and Unchained Memories (2003).
Unchained Memories is a 2003 documentary film about the stories of former slaves interviewed during the 1930s as part of the Federal Writers' Project and preserved in the WPA Slave Narrative Collection.
 This HBO film interpretation directed by Ed Bell and Thomas Lennon is a compilation of slave narratives, narrated by actors, emulating the original conversation with the interviewer.
 The slave narratives may be the most accurate in terms of the everyday activities of the enslaved, serving as personal memoirs of more than two thousand former slaves.
 The documentary depicts the emotions of the slaves and what they endured.
 The "Master" had the opportunity to sell, trade, or kill the enslaved, for retribution should one slave not obey.
"Django Unchained" is a 2012 American western film written and directed by Quentin Tarantino.
 It stars Jamie Foxx as Django, a freed slave, who teams up with a bounty hunter called Dr. King Schultz (Christoph Waltz) to free his wife from plantation owner Calvin Candie (Leonardo DiCaprio).
 "Django Unchained" was screened for the first time at the Directors Guild of America on December 1, 2012.
 Its official premiere was cancelled in the wake of the Sandy Hook Elementary School shooting and was replaced with a screening for the cast and crew.
 "Django Unchained" was released on December 25, 2012 in the United States and on January 18, 2013 in the United Kingdom.
 As of December 7, 2013, "Django Unchained" has earned over $425 million at the box office.

Question: Which documentary film was released first, Unchained Memories or What Remains of Us?
Answer: Unchained Memories