Back in 2007, SM Entertainment debuted their newest girl group known as So Nyeo Shi Dae (SNSD) who are better known internationally as Girls' Generation. Consisting of nine members - Taeyeon, Tiffany, Sunny, Jessica, Hyoyeon, Yuri, Yoona, Sooyoung, and Seohyun - at the time (Jessica would leave in 2014), they debuted when girl groups were considered second class to boy bands. Girls' Generation changed that as they were often on par (or at times surpassing) with their male counterparts.

Ultimately, Girls' Generation would innovate what a K-pop girl group is.

Their contributions would help bring rise to today's generation of powerful girl groups such as Black Pink, Mamamoo, Red Velvet, and many others.

As for 2017, it marks a huge milestone for Girls' Generation as they celebrate their 10-year anniversary. To celebrate, they will release their sixth long play (LP) or full-length studio album titled "Holiday Night."

Girls' Generation teases their comeback by looking back on their careers

Pre-release promotions for "Holiday Night" were overly abundant but also a bit different compared to other comebacks. It was abundant as each member highlighted her very own set of promotional images, about five or six each.

Promotions were also a bit different as each member gave a short confessional video to describe their experiences over the past decade.

On July 27 at midnight KST, Yoona was revealed to be the first member and she described her "happiest moments" being in Girls' Generation. The other members were featured subsequently. Ultimately, the short confessional video concluded with Sunny on August 3 at midnight KST. She talked about their first performances, how chaotic and nervous they were at first but eventually getting to the point they are at now because they worked hard and enjoyed it.

They also held a special live broadcast on V Live titled "Girls' Generation PARTY Night." This was their way of saying "thank you" and being interactive with fans not just in South Korea but around the world.

They reminisced about the last ten years, performed snippets of their upcoming comeback, and even celebrated Tiffany's birthday as she turned 28-years-old on August 1, 2017.

K-pop fans think Girls' Generation's concept has something to do with mermaids

SM Entertainment and Girls' Generation released more than enough teasers to keep K-pop fans satisfied, especially that part of their fan club known as Sones. They were also very careful not to make sure the concept for their 10-year anniversary come back remained an enigma.

Ergo, many K-pop fans are wondering and anticipating what "Holiday Night" will feature as a concept. Many of them hypothesize Girls' Generation will be mermaids or have something to do with the sea.

To back their hypotheses, they bring up the recent social media activity on the girl group's personal pages - specifically Taeyeon and Seohyun. Starting with the former, Taeyeon has changed the "about me" section of her Instagram to fish. She even posted a picture showing a strand of her hair shaped into a fish symbol.

As for the latter, Seohyun posted an image in which the entire caption consisted of sea emoticons which were reposted later on by Hyoyeon. Seohyun also posted a video talking about how she wants to be a mermaid.

K-pop fans will not have to wait long to find out what "Holiday Night" will feature as it releases on August 7, 2017. It will utilize the popular concept of duel title track often used by the more popular K-pop acts. For Girls' Generation's 10-year anniversary come back, they are "All Night" and "Holiday."