What is "Pattichha Samuppadha" in buddhism i want clarification about what is "patichcha samuppada" its in 

"Anekajati sansaram  sandhavissam anibbisam
Gahakarakam gavesanto dukka jati punappunam"

“This tour, this cycle of existence, has run
 through numerous births without encountering,
 looking for the builder, the creator of the world
 and self. For, repeated birth is painful.”

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Pratityasamutpada means "gradual auto-emerging". It describes the process by which a newborn baby develops subjective experience of "I" and "desirable/undesirable objects" and "the world".

Information is an ever-present part of the universe. All physical interactions carry information. As these interactions have some amount of regularity (they repeat in patterns) - the baby accumulates information.

As information accumulates, it becomes more and more complex and integrated, until it can reflect or represent something about the world. Now it can be called "mind".

This process evolves until it culminates in recognition, when the baby can recognize something from before, and associations when it can relate things that were somehow connected before.

The process evolves further until the baby develops notions of objects or entities, each having a stable identity. The baby begins classifying these objects as "desirable" and "undesirable" based on experience of peace or disturbance that they bring. It starts pursuing desirable objects and avoiding undesirable.

Then gradually the baby develops a notion of "I", as the subject that experiences contact with the objects, and as the entity that pursues an object and enjoys the result.

In the baby's mind there is entire world, with people, objects, problems, and happy moments. It grows, matures, gets old, and dies.

Then the cycle restarts when a new baby is born. It starts from scratch again, going through the same process. This goes on indefinitely.

Every generation starts with complete ignorance of the fact that nothing completely disappears and nothing appears from scratch, and that everything keeps transforming from one form to another. Every person grows up assuming that he or she is completely separate from everyone and everything else. Then they begin pursuing some selfish goals and fighting with each other. The cycle repeats on and on.

If only they knew that this world of separation is an illusion! They would teach their children to live differently! No pursuit of stupid material goals, no fear of death, no fighting, no murdering the planet! But they don't know and so the cycle goes on and on and on...

This is "the cycle of existence" that "has run through numerous births".


  Thus, this twelvefold dependent arising — which comes from several different causes and conditions, is neither permanent nor impermanent, is neither compounded nor uncompounded, is not without cause or condition, is not an experiencer, and is not something exhaustible, something destructible, or something that ceases — has proceeded from time immemorial, without interruption, like the flow of a river. - The Rice Seedling Sutra.


Now, if you look at this process from afar, you will see that it's not really about an individual baby, it is about the overall pattern of subjective experience emerging from information and then taking its model of reality for reality itself. The exact way this happens, the reason it relates to Buddhist Ethics, and the way to undo it, is the heart of hearts of Buddhism.