Naga means snake and other names are Bhujanga etc. Lord Shiva is worshipped in the form of Nageswara, one of the twelve Jyotirlinga (Shiva Linga’s giving the light of knowledge). In this form, He is the Lord of all the snakes. These snakes also symbolise the “Kundalini Shakti” of the spinal column. Whereas Nagaraja is the king of all snakes, their supreme form is the thousand hooded “Seesha” Who coils into a bed for Narayana to sleep or is always guarding Him. In turn there are eight such Naga kings starting with Sesha the eldest, Vasuki the second born and so on.
शेषॊ ऽनन्तॊ वासुकिश च तक्षकश च भुजंगमः | कूर्मश च कुलिकश चैव काद्रवेया महाबलाः || Mahabharata Adi Parva:I.59.40
[among the Nagaraja] Shesha, Ananta, Vasuki, Taksaka, Kurmasa and Kulika, these six sons of Kadru and very strong and powerful. Another sloka says these are sons of Surasa who gave borth to the divine Nagas while Kadru gave birth to 1000 nagas and sarpa.
सुरसा अजनयन् नागान् राम कद्रूः च पन्नगान् ॥३-१४-२८॥ According to this Surasaa gave birth to the Nagas while Kadru gives birth to the Pannaga. Both Naga and Pannaga are snakes but of different kinds. Naga raise their heads high while the Pannaga always stoop low. Uraga are those with human faces! So some of these superior Naga are Uraga and can change form (iccha-dhari naga).
Patala or Nagaloka is their general residence but they are in all the tala.
People suffer from the curse of serpents by having a malefic Rahu eclipsing and troubling the luminaries. Its aspect or eclipse of the Sun destroys wealth and brings abject poverty, financial downturns etc. Its eclipse and affliction of the Moon destroys health and brings terrible diseases. Its affliction of Jupiter destroys intelligence and brings ill-repute. In this manner, the curse of the snakes can be very troublesome for a person and remedial measures are prescribed.
Terrible malefic combinations like Kala Sarpa Yoga (KSY) can bring untold suffering and the adverse circumstances can convert an otherwise good person into a criminal. The Kala Amrita Yoga gives terrible suffering that results in renunciation and later a spiritual path is promised. Sarpa Yoga is formed by the presence of three or more malefics in quadrants to the Lagna and the resultant suffering can be very bad. In all such circumstances we look for the natural benefic planet in the first or seventh house, or conjoining the malefic combination and destroying the venom of the snakes. Jupiter causing the break results in Padma Yoga (Lotus blooms) or Maha Padma Yoga. Moon causing the break results in Sankha Yoga (Conch) or Mahasankha Yoga etc.
The eight mantras on the basis of the Astadala Padma and the Kala-Chakra are given below for the benefit of the readers. If these mantras are recited by the person troubled by the Sarpa and other such Yoga or during Rahu Dasa or in times of trouble, the Divine Serpents come to his rescue and bless him with good fortune, strength and good reputation.
For example, if Mercury is afflicted by Ketu and associates with the house of enemy, then like Raja Nala the native suffers the bite of Karkotaka Naga making his body deformed and ugly. This suffering is due to Indra deva asking Karkotaka to destroy Nala.
ॐ स्वेताय विप्रवर्नाय सहस्रफणाय शेषाय नमः।
om svetāya vipravarnāya sahasraphaṇāya śeṣāya namaḥ|
ॐ पीताय क्षत्रियवर्णाय सप्तसतफणाय वसुकये नमः।
om pītāya kṣatriyavarṇāya saptasataphaṇāya vasukaye namaḥ|
ॐ नीलाय वैश्यवर्णाय पञ्चसतफणाय तक्षकाय नमः।
om nīlāya vaiśyavarṇāya pañcasataphaṇāya takṣakāya namaḥ|
ॐ कृष्णाय वैश्यवर्णाय सप्तसतफणाय संखपालाय नमः।
om kṛṣṇāya vaiśyavarṇāya saptasataphaṇāya saṁkhapālāya namaḥ|
ॐ उज्जवलाय शूद्रवर्णाय पञ्चसतफणाय महापद्माय नमः।
om ujjavalāya śūdravarṇāya pañcasataphaṇāya mahāpadmāya namaḥ|
ॐ उज्जवलाय शूद्रवर्णाय त्रींसतफनाय कम्बलाय नमः।
om ujjavalāya śūdravarṇāya trīṁsataphanāya kambalāya namaḥ|
ॐ उज्जवलाय शूद्रवर्णाय त्रींसतफनाय कर्कोटकाय नमः।
om ujjavalāya śūdravarṇāya trīṁsataphanāya karkoṭakāya namaḥ|