Rather than being one large monolithic “religion,” Hinduism is an umbrella under which a number of different schools of thought exist. Academics categorize contemporary Hinduism into four major denominations: Vaishnavism, Shaivism, Shaktism and Smartism. The denominations differ primarily in the understanding and worship of the Supreme or Absolute Truth. However from a broader philosophical perspective there are just two main underlying spiritual perspectives, One is the Vaisnava philosophy and the other is that of Adi Shankara known as Mayavada or Advaita philosophy. Amongst these different traditions or branches, Vaishnavism* is perhaps the largest branch, with hundreds of millions of adherents and countless sub-branches. All of them, however have some common characteristics and foundational philosophical beliefs. To understand and appreciate this is very challenging for people raised in or only exposed to the traditional Christian concept of religion, which is by nature very “centralized” and exclusive.
A good vehicle to help a Westerner learn more about Hinduism is by comparing it to a religion that they do have some familiarity with. For America, that would be comparing Hinduism to Christianity and some of the similarities and differences.
For a comparative study please read the following articles
Gurus and Disciplic Traditions
Vaishnavas recognize that despite the various ways and methods that different acharyas teach, the apex of perfect yoga, and the ultimate goal of the human form of life, is the achievement of pure bhakti, or spiritual love. Yoga can be simply compared to a ladder. The lowest rung is yoga asanas and the highest rung—the culmination and definition of yoga—is perfect spiritual love.