“Yoga means that which joins or yokes. Purusha is that which has a body. Planetary Yogas connect the Purusha with Karma Phalas (the results of actions). From their permutations, planets indicate how the Purusha is yoked to Karma Phala.” – Prasna Marga: 9, 48
Thus Prasna Marga succinctly tells us exactly what a Yoga is. Yogas are off four types: Foundational Yogas, Named Yogas, Unique Bhava Yogas and Redundant Bhava Yogas.
Foundational Yogas are those planetary configurations that set us up to strong or weak foundation. Those Foundational Yogas which yoke us to a strong foundation help us to grow into happier, more successful people who are able to make the most of our opportunities and abilities. Those Foundational Yogas which yoke us to a weak foundation temp us to greater decay, lesser happiness and squandering our abilities and the opportunities that life gives us. Foundational Yogas are not Dasa dependent, which means, they are not used for timing the good and bad periods in life. Favorable Foundational Yogas make all the good stuff in our charts better and the bad stuff less malignant. Difficult Foundational Yogas make all the good stuff in our charts less and the bad stuff more significant. Foundation Yogas consist of Nabhasa Yogas, Pancha Mahapurusha Yogas, Solar Yogas, Lunar Yogas, Lagna Yogas, Malika Yogas as well as a few other miscellaneous Yogas. These Yogas are all very, very important and must be learned by every astrologer who wishes to know where their client is at in this lifetime. In my opinion, an astrologer who does not know these Foundational Yogas has no business reading horoscopes as they will simply not be able to see into the heart of the person. Nabhasa Yogas are of the greatest importance.
In addition to the Foundation Yogas there are also some important Yogas that are used for timing events with the Dasas, but which also reveal many foundational strengths and focuses. These are very important Yogas, such the Yoga Karakas principles of auspicious and inauspicious house lords. These Yogas are amongst the most important Yogas to learn as they will be present in every horoscope.
Next in importance are the Named Yogas. These are the Yogas that are actually given specific names by the ancient astrologers, such as Laksmi Yoga, Parvata Yoga, Gaja Kesari Yoga, etc. There are approximately 108 such Yogas. These Yogas are important and signaled out by their special names due to their having a twofold effect in the horoscope: They have a character building foundational effect as do the Foundational Yogas, though to a lesser degree of importance; and they are Dasa dependent, which is to say, they are used for predicting future events. These Yogas particularly indicate periods of success, wealth and upliftment. Every astrologer will eventually want to learn all these Named Yogas – though learning the Foundational Yogas is a much higher priority.
After the astrologer learns his Astrological Components well and learned some systematic systems of predictions with which to tackle any question, they will naturally aspire to specialize in some area of greatest interest to them be it Relationship Astrology, Financial Astrology, Medical Astrology, Predicting Elections, etc. To help in this specialization the ancient astrologers have given us literally hundreds of Yogas for each Bhava with specific effects for each area of life that we could imagine. These Yogas are great snap-shot techniques for helping us predict correctly in these defined areas. These Yogas, however, are not all created equal. 90% of these Yogas are simply redundant principles that an astrologer who learns a scientific system of astrology need not burden himself with. In the dark middle ages astrologers regularly learned to read a horoscope by memorizing as many Yogas as they could, memorizing literally thousands of Yogas. In the past 150 years or so with the dawn of our solar system having moved appreciably closer to the Galactic Center (the center of Universal Intelligence in our galaxy) astrologers are relearning the ancient and holistic predictive systems of Parasara and Jaimini which have been largely ignored in preference of learning Yogas during the past 2-3000 years. Now, relying on intelligence and understanding over blind memorization, the astrologer is better off learning astrological systems and ignoring all these Redundant Bhava Yogas. 10% or so of these Yogas, however, are very unique. They do not seem to follow the rules outlined by the systematic schools of Parasara and Jaimini – and they work. The astrologer who is ready to specialize in some area will do well to learn these handfuls of Unique Bhava Yogas. Many times one of these Yogas will just pop out on us as we read a chart and spell out the answer perfectly.