Lord Shiva is the third god in the Hindu Trinity (Brahma, Vishnu, Shiva). He represents the aspect of supreme being that continously dissolves and recreates the universe.

He is also known by different names - Eshwar, Mahadeva, Vishwanath, Shankar, Nataraja, Bhairava and so on. Shiva Lingam which is a symbol of Lord Shiva is often worshipped instead of he Lord.

Many Shiva Temples have the Shiva Linga as the main deity. Maha Shivaratri is an important day for the devotees of Lord shiva. During that day, the devotees stay awake through out the night praying to the Lord. All through the day the devotees abstain from having any food and worship the Lord.

After performing the traditional poojas in the morning they break their fast. this day is considered especially auspicious for women. Goddess Paravthi/Shakthi is the wife of Lord Shiva.

Slokas on Lord Shiva

Thathpurushyaaya Vidhmahe 
Mahadevaaya Dheemahi 
Thanno Rudra(h) Prachodayaath  
 
Aum Trayambakam Yajaamahey
Sugandhim Pusti Vardhanam
Urvaarukamiva Bandhanaath
Mrutyor Muksheeya Maamritaat

Kailaasarana Shiva Chandramouli
Phaneendra Maathaa Mukutee Zalaalee
Kaarunya Sindhu Bhava Dukha Haaree
Thujaveena Shambho Maja Kona Taaree

Mrutyunjayaaya Rudraaya
Neelakantaaya Shambhave
Amriteshaaya Sarvaaya
Mahadevaaya Te Namaha

Gauri Vallabha Kaamaarey
Kaala Koota Vishaasana
Maam Uddhhare Padambhoje
Tripura Agnyata Kaantaka

Vandhe Sambumumapathimh suragurum
Vandhe Jagathkaaranam
Vandhe PanaBhooshanam mruhadharam
Vandhe Pasoonaam pathim
Vandhe Soorya Shasaankavahninayanam
Vandhe Mukundhapriyam
Vandhe Baktha Janasrayamsvratham
Vandhe Shivam Sankaram