Supergirl is an American superhero action-adventure television series developed by Ali Adler, Greg Berlanti and Andrew Kreisberg (the latter two having previously created Arrow and The Flash) that originally aired on CBS and premiered on October 26, 2015. It is based on the DC Comics character Supergirl, created by Otto Binder and Al Plastino, and stars Melissa Benoist in the title role. Supergirl is a costumed superheroine who is Superman’s cousin and one of the last surviving Kryptonians. The series is set in the Arrowverse, sharing continuity with the other television series of the universe.
The series was officially picked up on May 6, 2015, after receiving a series commitment in September 2014, and received a full season order on November 30, 2015. On May 12, 2016, Warner Bros. announced that the series had been renewed for a second season and that it would move from CBS to The CW. It debuted on October 10, 2016. On January 8, 2017, The CW renewed the series for a third season, which began airing on October 9, 2017. From Wikipedia
No of Seasons 1 to 4
No of DVDs 6