Caṇḍī or Caṇḍīika is the name by which the Supreme Goddess is referred to in Devi Mahatmya. According to Coburn, "Caṇḍīika is "the violent and impetuous one". In the light of the primacy of this designation of the goddess, it is striking that the word Caṇḍīka has virtually no earlier history in Sanskrit. There are no instances of its occurrence in the Vedic literature we have surveyed. The epics are similarly barren: neither the Ramayana nor the Mahabharata give evidence of the epithet, although in one of the hymns inserted in the latter Caṇḍa and Caṇḍī are applied to the deity they praised."
The reason for the absence of the name Chandi in any ancient Sanskrit work is because of the deity belonging to the non-Sanskrit or non-brahminical tradition of Hinduism, and originates in Bengal as a non-aryan tribal deity, which is further explained below.
The designation of Chandi or Chandika is used twenty-nine times in the Devi Mahatmya, which is agreed by many scholars to have had originated in Bengal, the primary seat of the Shakta or Goddess tradition and tantric sadhana since ancient times. It is the most common epithet used for the Goddess. In Devi Mahatmya, Chandi, Chandika, Ambika and Durga have been used synonymously.
The origin of the Goddess is given in the second chapter of Devi Mahatmya.
"The great Goddess was born from the energies of the male divinities when the gods became impotent in the long-drawn-out battle with the asuras. All the energies of the Gods became united and became supernova, throwing out flames in all directions. Then that unique light, pervading the Three Worlds with its lustre, combined into one, and became a female form."
"The Devi projected an overwhelming omnipotence. The three eyed goddess was adorned with the crescent moon. Her multiple arms held auspicious weapons and emblems, jewels and ornaments, garments and utensils, garlands and rosaries of beads, all offered by the gods. With her golden body blazing with the splendour of a thousand suns, seated on her lion vehicle, Chandi is one of the most spectacular of all personifications of Cosmic energy." 
In other scriptures, Chandi is portrayed as "assisting" Kali in her battle with demon Raktabija. While Kali drank Raktabija's blood, which created new demons on falling on the ground; Chandi would desstroy the armies of demons created from his blood and finally killed Raktabija himself. In Skanda Purana, this story is retold and another story of Chandika killing demons Chanda and Manda is added.
The dhyana sloka preceding the Middle episode of Devi Mahatmya the iconographic details are given. The Goddess is described as eighteen armed bearing string of beads, battle axe, mace, arrow, thunderbolt, lotus, bow, water-pot, cudgel, lance, sword, shield, conch, bell, wine-cup, trident, noose and the discus (sudarsana). She has a complexion of coral and is seated on a lotus.
In some temples the images of Maha Kali, Maha Lakshmi, and Maha Saraswati are kept separately. The Goddess is also portrayed as four armed in many temples.
Temples devoted to Chandi are located in many places including the following:
- Gandaki Chandi, Gandaki near Pokhara, Nepal. (Shakti Peethas)
- Mangal Chandika, Ujjaani, West Bengal. (Shakti Peethas)
- Saptashrangi Temple, Vani, (Maharashtra). (Ashtadasa Bhuja Mahalakshmi)
- Mahalaxmi Temple, Mumbai (Maharashtra). (Three separate images).
- Hemadpanthi Chandika Devi Mandir,Katol (Maharashtra).
- Vaishno Devi temple, Khatra, Jammu and Kashmir. (Three Pindas (stones)).
- Katak Chandi Temple, Cuttack, Orissa. (Four armed).
- Ashtadasa Bhuja Mahalakshmi temple, Skandhashramam, Salem, Tamil Nadu.
- Mangal Chandi temple, Guwahati, Assam.
- Mangal Chandi temple, Chandithala, Kolkata.
- Chandi Devi Temple, Neel Parvat, Haridwar 
- Chandi Mandir, Chandigarh. The city of Chandigarh (lit. "fort of Chandi") derives its name from this temple.
- Chandi Mata Mandir Machail, Kishtwar,J&K Sphire valley Paddar
- Chandi Mata Mandir Chinnot, Badherwah,J&K
In folklore of Bengal
Chandi is one of the most popular folk deities in Bengal, and a number of poems and literary compositions in Bengali called Chandi Mangala Kavyas were written from 13th century to early 19th century. These had the effect of merging the local folk and tribal goddesses with mainstream Hinduism. The Mangal kavyas often associate Chandi with goddess Kali or Kalika. and recognize her as a consort of Shiva and mother of Ganesha and Kartikeya, which are characteristics of goddesses like Parvati and Durga. The concept of Chandi as the supreme Goddess also underwent a change. The worship of the goddess became heterogeneous in nature.
Chandi is associated with good fortune as well as disaster. Her auspivcious forms like Mangal Chandi, Sankat Mangal Chandi, Rana Chandi bestow joy, riches, children , good hunting and victory in battles while other forms like Olai Chandi cure diseases like cholera, plague and cattle diseases.
These are almost all village and tribal Goddesses with the name of the village or tribe being added on to the name Chandi. The most important of these Goddesses is Mangol Chandi who is worshipped in the entire state and also in Assam. Here the word "Mangol" means auspicious or benign.
- ^ Coburn, Thomas B., Devī Māhātmya. p 95
- ^ Coburn, Thomas B., Devī Māhātmya.
- ^ Mookerjee, Ajit, Kali, The Feminine Force, p 49
- ^ Wilkins p.255-7
- ^ Wilkins p.260
- ^ Sankaranarayanan. S., Devi Mahatmyam, P 148.
- ^ Chandi Devi Haridwar.
- ^ McDaniel(2004) p.21
- ^ McDaniel(2004) pp. 149-150
- ^ McDaniel(2002) pp. 9-11
- ^ Manna, Sibendu, Mother Goddess, Chaṇḍī, pp. 100-110