Yoga is a path of self-discipline (anushasanam) that one chooses to walk, in order to reveal the meaning of the word consciousness (prajna). Consciousness is a word pointing towards something difficult to express with language. Being an abstract word it is only understood through direct experience. However it can be described as the underlying awareness which is masked by thoughts and mental structures born from identification, fear and attachment. When the mind and body are in stillness and are not impeding this awareness, it is able to experience itself in its true form (svarupa) which can be described as reality, spaciousness, expansiveness, dynamic, energy, vital, endless, formless, omniscient, etc.
There is only one yoga, and its purpose is to reveal this pure consciousness (sat citta). Different teachers have shared their experiences differently. Our teachings have their source in the great masters T. Krishnamacharya and Acharya BKS Iyengar, and both of them shared the wisdom of the Vedas, the Vedanta and the Yoga Shastras, particularly the teachings of Patanjali Muni or Sage Patanjali.
You can find out more about yoga here and about Patanjali’s eight petals of yoga here, and the Iyengar tradition here.