Maa Shailputri is the absolute form of Mother Nature.
She is also known as Goddess Parvati, the consort of Lord Shiva and mother of Ganesha and Kartikeya (Murugan).
In the Navratri festival the worshiped Mother Goddess has a half moon in her forehead & she is holding a trident in her right hand & lotus flower in her left hand. She rides on a mount Nandi, a bull.
In some scriptures like Shivapurana & Devi Bhagvatam the story of Mother Goddess is written as follows: Maa Bhagwati in her earlier birth was born as a daughter of Daksh Prajapati.
Then her name was Sati and she was married to Lord Shiva.
But in a sacrificial ceremony organized by her father Prajapati Daksh, she got her body burnt in the yogic fire, because she could not bear the insult of her husband Lord Shiva by her father Prajapati Daksha in the sacrificial ceremony.
In her next birth she incarnated her as Goddess Parvati, the daughter of Parvatraj Himalaya and among Nava Durgas she has been referred to as Shailaputri who was again known as Himavati.
In her Himavati aspect she defeated all prominent gods.
Like her pervious birth in this life also Maa Shailaputri (Parvati) got married with Lord Shiva. The first and the most prominent among Nava Durgas, Shailaputri is of immense importance and her glories are endless. On the first day of Navaratri worship it is she who is worshiped.
She is the Devi of the root chakra, who, upon awakening, begins her journey upwards.
Sitting on Nandi, and making her first journey from the Muladarachakra. As from her father to her husband – the awakening Shakti, beginning Her search for Lord Shiva or making a move towards her Shiva.
So that, in navaratri pooja, the first day yogi’s keep their mind concentrated on Muladhara. This is the starting point of their spiritual discipline. They start their Yogasadha from here. Shailaputri is the Muladhara Shakti to be realized withing Self and sought for higher depths, in the yogic meditation.