In Iyengar yoga there are about 200 postures (asanas) which are practiced by students all over the world. All Iyengar teachers use the tradional Sanskrit names of the asanas so wherever you are in the world you can join a class and the names will be familiar.
The postures (asanas) are divided to groups in which each group has its own sequences. The classes therefore are not routine but varied and divided according to levels of difficulty that can be practiced by beginners and up to advanced stages.
Pranayama is a compound word in Sanskrit composed of 'prana' + 'ayama'. Prana is the cosmic/ universal life force which is responsible for keeping us 'alive'. In India, when a person dies, we say that 'prana has left the person's body. The word 'ayama' has two different meanings - to stretch/ elongate/ expand and to control/ restrain. Breath is a gross manifestation of this prana. So, the word pranayama means the ability to expand or stretch our life force (prana) by controlling the breath. Pranayama techniques involve controlling the breath in a variety of ways.
Pranayama is the fourth of the eight limbs of yoga (Ashtanga Yoga) as defined by Sage Patanjali. It provides a vital bridge between the body and the mind. By controlling the breath, one can control the mind.