Britney Spears thanked her fans for two decades of support yesterday as her hit single "...Baby One More Time" turned 20-years-old.

"It’s hard to put into words what today means to me… 20 years ago, the world heard my music for the very first time!" Britney wrote on Instagram, along with behind-the-scenes footage from the music video. "So much has happened since then… but what I really want to say is thank you to my amazing fans who have been there for me since day 1. Your support over the years has meant the absolute world to me!! Love you all!"

In 1998, a then 16-year-old Britney hit the scene in her pigtails and now notable school girl outfit -- arguably changing the pop music era and catapulting her to the title of "Princess of Pop."

"...Baby One More Time" appeared on the singer's debut album of the same name and the song topped the charts in 19 countries, according to ABC Radio.

PHOTO: Britney Spears is pictured at Z100's 5th Annual "Jingle Ball," Dec. 17, 1998.
Ron Galella/Getty Images
Britney Spears is pictured at Z100's 5th Annual "Jingle Ball," Dec. 17, 1998.
It’s hard to put into words what today means to me… 20 years ago, the world heard my music for the very first time!
PHOTO: Britney Spears attends the announcement of her new residency, "Britney: Domination" at Park MGM on Oct. 18, 2018 in Las Vegas, Nevada.
Gabe Ginsberg/Getty Images
Britney Spears attends the announcement of her new residency, "Britney: Domination" at Park MGM on Oct. 18, 2018 in Las Vegas, Nevada.

In celebration of the anniversary, the album is being released on picture vinyl for the first time and is not available for pre-order on Amazon.

For $299.95, Britney superfans can also grab the "...Baby One More Time" collector's edition bundle on her website, which includes a personalized plaque, special edition hoodie and t-shirt, tote, embroidered hat, key ring and the Limited Edition 20th Anniversary Vinyl.

PHOTO: Britney Spears in a screengrab from her music video "Baby One More Time."
Britney Spears via YouTube
Britney Spears in a screengrab from her music video "Baby One More Time."

Britney recently announced her new Las Vegas residency show, Domination, at the Park MGM, which will open in February.