A rudraksha is the seed of the Eliocarpus ganitrus- is a large evergreen broad-leaved tree whose seed is traditionally used for prayer beads in Hinduism and Buddhism. The seeds are known as rudraksha, or rudraksh.
Rudraksha is the seed of species which mainly grow in Himalayan. Also found in Nepal, Thailand, or Indonasia. The quality of Rudraksha depends where it grow- It is said that Himalayan soil and atmoshpeher is best for Rudraksha. Rudraksha beads have between 1 and 21 lines (mukhi),- have different meaning and is used for various purpose.
Rudraksha Beads- Usually, each mala has 108 beads and 1 Bindu bead tied into a thread- Cotton and Silk. The extra beads also known as a Guru Bead; helps mark the beginning and end of a cycle of 108 also has symbolic value as a 'principle' bead. The Mala considered scared and its worth to mention that the rudraksha may be damaged if strung too tightly.
Once: Sage Bhusunda (Sanatkumara) asked Lord Kalagni Rudra: “What is the origin of the Rudraksha seeds, and what are the effects of wearing them?”
Lord Kalagni Rudra answered: “When, in order to destroy the Tripura demons, I closed My eyes, tears fell from them to the ground and became Rudrakshas for the benefit of all.” Source - The Rudraksha Jabala Upanishad
It is said that Rudraksha dilutes the negative energy- a shield against negative energies and promote well-being and positive energy. A guru usually energizes a rudraksha in different ways for different kinds of people. Rudraksha helps and provides good support to people who are on the spiritutal path. Legend says that Siva awoke after a thousand years of meditation and began to shed tears of worldly-wise compassion, these tears crystallized into seeds and there grew the first Rudraksha tree. "The Eye of Shiva" a tree seed considered sacred to Shiva and worn by worshippers of Shiva, Shakti, and Ganesha, and by yogis, Rudraksha enhances one’s intellect and self-awareness It is extensively used for wearing and chanting mantras It cultivates Wisdom and intellect.
On the contrary- wearing the wrong can could disturb one's life so be careful and take proper consideration before you put any type of Rudraksha beads or bracelet.