"Get your muzzle out of those books and make some friends!" That's what Princess Celestia tells Twilight Sparkle. She may be the smartest unicorn in Equestria, but Twilight Sparkle gets an "incomplete" in friendship. There's more to life than learning magic, after all -- so she goes to Ponyville on a mission to make friends. There she meets five special ponies who take her on exciting adventures and teach her the most powerful magic of all ... the magic of friendship!
In each episode, the Mane Six ponies (or in other cases, other characters) go on adventures in Equestria and learn lessons in friendship. Each season starts off with a two-part story (comprising of two episodes), with most focusing on Twilight Sparkle. Originally in Season 1, Twilight writes all the letters to Princess Celestia about friendship. In Seasons 2-3, her pony friends (and Spike) write the letters to her. From the Season 3 finale onwards, Twilight graduates from being a student of Princess Celestia and becomes an Alicorn princess, then by the end of the show's first era (2010-2014) in the Season 4 finale, acquires her own castle, the Castle of Friendship.
The second generation of this show, which starts off with Season 5, introduces Starlight Glimmer, who learns lessons in friendship of her own throughout Season 6, then begins having adventures with her new friends in Season 7. To educate various ponies and creatures in Equestria, the School of Friendship is introduced for Season 8. Finally, Twilight and her friends defeat evil for good in Season 9, and many years later, Twilight becomes the new ruler of Equestria.
May 19, 2009: The Mane Six was originally going to be the Mane Nine -- Twilight Twinkle, Applejack, Cherilee, Fluttershy, Pinkie Pie, Rainbow Dash, Rarity, Scootaloo, and Sweetie Belle.
June 22–July 10, 2009: An unreleased Animation Test titled "My Little Pony Adventures" (codenamed "MLPTST") was made. It featured Twilight, Pinkie and Rainbow Dash. Twilight's final design was first used in this film.
September 10, 2009: A "My Little Pony Adventures" show bible existed.
Season 1 (2009-2011)
August 31, 2009: The first draft of the script for the first two episodes was written by Lauren Faust.
February 23, 2010: The first episode's animatic was completed.
March 29, 2010: The title "My Little Pony: Friendship is Magic" was first mentioned in an article at the Broadcasting & Cable website.
September 1, 2010: The first screenshots of the show were leaked online.
September 15, 2010: The show was set to air its first episode on October 10, 2010.
September 28, 2010: A somewhat early version of the very first opening animation of the show was unveiled online at Hasbro.com. The following day, videos of the characters were also unveiled.
March 18, 2011: Production of this season concluded.
Season 2 (2010-2012)
May 28, 2010: Production of Season 2 began on this date, starting with the first two episodes with a working title of "Seeds of Chaos".
October 8, 2010: As of two days before the show's first episode premiered on The Hub, the first half of Season 2 was already currently in production, with the first eight episodes having made it through their first drafts.
December 14–15, 2010: This season's first episode's animatic was completed.
May 8, 2011: Lauren Faust, creator of the show, was downgraded from executive producer to consulting producer, beginning within Season 2.
August 22, 2011: Season 2's release date of September 17 was confirmed. At that time, all episodes except the last two have made it to the animatic stage, and about eight episodes have made it to the rough-cut stage.
March 23, 2012: Production of this season concluded.
Season 3 (2011-2013)
June 3, 2011: Production of Season 3 began on this date with the premises of the first three episodes.
August 9, 2011: The first draft of a Season 3 episode's script was written.
January 26, 2012: This season's first episode's animatic was completed.
May 1, 2012: All 13 episodes have made it to the animatic stage.
July 18, 2012: Season 3 was delayed to a later date. At that time, eight episodes have made it to the rough-cut stage.
October 18, 2012: Season 3's release date of November 10 was confirmed. Shortly afterwards, production of this season concluded by November.
Season 4 (2012-2014)
May 4, 2012: Pre-production of Season 4 occurred on this date, with the first premises submitted.
July 10, 2012: The first drafts of the scripts for Season 4's first two episodes were written.
February 5, 2013: Season 4 was confirmed for 26 episodes.
April 15, 2013: This season's first episode's animatic was completed.
July 25, 2013: Season 4's release date of November 23 was confirmed. At that time, about 16 episodes have made it to the animatic stage.
March 19, 2014: Production of this season concluded.
Season 5 (2013-2015)
October 11, 2013: Pre-production of Season 5 occurred on this date, with the first few premises written.
December 6, 2013: The first drafts of the scripts for Season 5's first episodes were written.
May 7, 2014: Season 5 was confirmed for a 2015 release, with another 26 episodes. At that time, 17 episodes have made it to the first-draft stage.
October 9, 2014: All Season 5 scripts were "locked polish".
November 3, 2014: The final song for Season 5 (possibly "Friends Are Always There for You") was in production.
October 16, 2015: Production of this season concluded.
Season 6 (2014-2016)
October 14, 2014: Pre-production of Season 6 occurred on this date, the day after Discovery Family launched.
December 2, 2014: The first drafts of the scripts for Season 6's first episodes were written, before Season 5 even premiered on the new Discovery Family channel.
September 19, 2015: Season 6 was confirmed for 26 episodes. At that time, all episodes except the last two had locked-polish scripts.
January 28, 2016: Season 6's release date was confirmed for the Spring of 2016.
August 22, 2016: Production of this season concluded.
Season 7 (2015-2017)
December 17, 2015: Production of Season 7 began.
January 19, 2016: The first drafts of the scripts for Season 7's first episodes were written.
October 5, 2016: All Season 7 scripts were "locked polish".
December 30, 2016: 26 episodes were confirmed for Season 7.
March 7, 2017: Season 7's release date was confirmed for April 15.
August 29, 2017: Production of this season concluded.
Season 8 (2016-2018)
August 12, 2016: Production of Season 8 began with the first premise.
September 22, 2016: The first drafts of the scripts for Season 8's first episodes were written, before Season 6's last episodes premiered on Discovery Family.
May 25, 2017: Season 8 was confirmed for a 2018 release, with another 26 episodes.
July 5, 2017: All Season 8 scripts were "locked polish", during Season 7's run of new episodes on Discovery Family.
May 31, 2018: Production of this season concluded, excluding the "Best Gift Ever" special.
September 10, 2018: The Best Gift Ever special completed production.
Season 9 (2017-2019)
August 8, 2017: Premises of 15 animated shorts for pre-Season 9 were written. In the end, only eight made it to the public. The first episodes got premises on September 12.
November 3, 2017: The first drafts of the scripts for Season 9's first episodes were written, before Season 8 even premiered on Discovery Family.
May 17, 2018: The last premises were submitted for approval. Six days later, Season 9 was publicly announced.
August 27, 2018: All Season 9 scripts were "locked polish".
February 16, 2019: Season 9 was confirmed to be the final season, resulting in a total of 221 episodes for the entire series (222 if you count "Best Gift Ever").
June 21, 2019: Production of the entire series offically concluded.
August 25, 2019: The last episodes were released (actually leaked) in the Netherlands, 1½ months before the official releases.
All My Little Pony: Friendship is Magic installments were originally broadcast on the Hub Network since its launch on October 10, 2010. Episodes were released simultaneously on iTunes since February 15, 2011. It was also available on Netflix since April 1, 2012.
The Hub Network was replaced by Discovery Family on October 13, 2014, shortly after The CW discontinued its Saturday morning cartoon block, Vortexx. Since then, most shows including My Little Pony were moved from the Hub Network to Discovery Family, and the show's second era that began with Season 5 has always originally aired on this network.
The final marathon of episodes aired on Discovery Family from December 23–30, 2019. The last episode to air was "The Last Problem" at 4:30 p.m. on December 30.