Some say that Paramamsa Yogananda 're-introduced' Kriya Yoga...

Yoganandaji was representing a lineage of teachers and was passing on a set of practices that had already been 'introduced' by them.

Being probably the most well-known Yogi in the West, it could be said that he introduced Kriya Yoga to the West.

Yogananda also made some adaptations to some of the Kriyas for Westerners as he felt that there was a difficulty for them to practice the original forms.

So, it would perhaps be more correct to say that Babaji reintroduced a specific set of Kriya Yoga practices through Lahiri Mahasaya (who was Yogananda's teacher's teacher).

Since then, there have been many Kriya teachers and schools that have come down from this lineage that began with Lahiri Mahasaya.

Paramahamsa Yogananda is perhaps still the most well-known representative of the Kriya teachings, due to his best-selling book 'Autobiography of a Yogi' and the organisation that he founded - the 'Self-Realization Fellowship' (or 'SRF').

Kriya Yoga practices are also taught by others teachers and lineages, although some of them may not call the practices 'Kriya Yoga'. 

For example Swami Sivananda's student Swami Satyananda Saraswati has taught and authored books that explain many Kriya techniques - these being in fact common to many Kundalini Yoga and Tantra practices.

Shiva - One of the Trinity, or 'the Supreme'?

'Shiva' - the 'auspicious' one

... to be continued .... :o)

Siva - Vasi - VaSiVaSiVaSiVaSiVaSi

In an 'esoteric' understanding of Saiva Siddhanta Yoga practice, 'Siva' (or 'Shiva') is not 'a god'...

Siva is energy and is the breath of life. 'Siva' is both life itself (as breath/'spirit') and the means to attune to the flow of life (through bringing attention to one's breath).

(Being representative of 'Spirit' or 'Source', Siva is also associated specifically with the Crown Chakra, or 'Sahasrara' Chakra.)

From the Sutra Jnanam by Valmiki Siddhar:

"What we are now in this eternal moment is the sacred Divine Breath, Vasi!"

What leads us to the infinite mind of the universe, through Ida and Pingala (the twin energy of Mother Kundalini), the left and right breath is this sacred Divine Breath, Vasi!

The One who posses this infinite universal mind is the Perfected Being, the Siddhar

Realizing all the living in the Universe as Sacred- as Siva, the Absolute is the Siddhar."