In the Hindu pantheon, Lord Shiva is the god of destruction, and a symbol of mercy. He is also very easily pleased. Shiva Mantra is mainly used to dispel fear; particularly the fear of change. Shiva mantra is chanted for the protection against diseases, sorrows, fears etc. Recitation of this Mantra gives success and Siddhis. Shiva Mantra has the power to boost a person's inner potential and strength. Shiva Mantra helps to cleanse the body, mind and soul of all the stress, rejection, failure, depression and other negative forces that we face in our daily lives. Shiva Mantra is to be chanted when one feels weak and drained of energy; both mental as well as physical. Shiva Mantra Japa is also an astrological remedy to ward of the negative influences of the Maraka planet in the birth horoscope. Many Mantras are devoted to Lord Shiva and each Mantra has its own special set of benefits.
Panchakshari Shiva Mantra
"Om Namah Shivaya"
This is perhaps the most well known among the Mantras dedicated to Lord Shiva. It is translated as 'I bow to Lord Shiva'. Chant this Mantra 108 times every day to purify your body and invoke the blessings of Lord Shiva.
Om Namo Bhagwate Rudraay
This is known as Rudra mantra. Rudra Mantra is recited to get blessing of Lord Shiva. It is considered effective for the fulfilment of one's wishes.
Shiva Gayatri Mantra
प्रणम्य शिरसा देवं गौरीपुत्रं विनायकम् । भक्तावासं स्मरेन्नित्यं आयुःकामार्थसिद्धये ॥ १॥
Shiv Dhyaan Mantra
Karcharankritam Vaa Kaayjam Karmjam Vaa Shravannayanjam Vaa Maansam Vaa Paradham I Vihitam Vihitam Vaa Sarv Metat Kshamasva Jay Jay Karunaabdhe Shree Mahadev Shambho II
This Mantra asks the Lord to forgive us from all kinds of sins we may have done
Maha Mrityunjaya Mantra
Om Tryambakam Yajamahe Sugandhim Pushti VardhanamI
Urvarukamiva Bandhanath Mrityormukshiya MamritatII
As the Lord of death and destruction, it is only fitting that we pray to Lord Shiva to help escape the fear of death. Maha Mrityunjaya Mantra helps us do just that.
Ekadasha Rudra Mantra
Ekadasha Rudra Mantra is a set of eleven Mantras. These Mantras are used to worship Lord Shiva in his various forms. These Mantras correspond to the months in a year. You will reap more benefits if you chant the Mantra specified for your month. But all the eleven Mantras can be recited too. It is an excellent practice to recite all the eleven Mantras on Shivaratri or during the time when Maha Rudra Yagnya takes place.
"Om HumHum Satrustambhanaya Hum Hum Om Phat" Pingala
"Om Shrim Hrim Shrim Sarva Mangalaya Pingalaya Om Namah"
"Om Aim Aim Mano Vanchita Siddhaya Aim Aim Om"
"Om Rudraya Roganashaya Agacha Cha Ram Om Namah"
"Om Shrim Hrim Sam Sam Hrim Shrim Shankarshanaya Om"
"Om Hrim Hrim Safalyayai Siddhaye Om Namah"
"Om Shrim Bam Sough Balavardhanaya Baleshwaraya Rudraya Phut Om"
"Om Hram Hrim Hum Samastha Graha Dosha Vinashaya Om"
"Om Gam Hluam Shroum Glaum Gam Om Namah"
"Om Chum Chandishwaraya Tejasyaya Chum Om Phut"
"Om Bhavod Bhava Sambhavaya Ishta Darshana Om Sam Om Namaha"