Vedas, the ancient Indian scriptures, describe desires elaborately. There are two kinds of desires - one is fundamental desire, the other topical desire. Topical desires arise in us more often than fundamental desires.  We like to eat sweets, watch movies, gossip with friends. These are topical desires. There are three desires under the fundamental category.
If we were to learn that today would be the last day in our lives, we would pray for another day. This is the first desire.
During my first talk on Bhagavad Gita in Madras, I was staying in a hotel. In the night, a young woman was had come to see me and began to speak in a hurry. "I left the home of my dominating mother-in-law today intending to commit suicide. The seashore was too crowded. If I tried to commit suicide then, someone would find me and save me. Just to spend a few hours before the next attempt,  I attended your talk on Bhagavad Gita.
"I heard you saying, every one wishes to live for a day more. That is utter nonsense! I have no desire to live another moment. Right now, I am going straight to seashore to drown myself!" she said and began to walk away.
I am a Monk! Imagine this - a young girl meets me in the night, that too at my hotel room and then goes to commit suicide! What would you make of it? I stopped her and said, "I have only dealt with the first half of what I planned to say today. Another half is yet to be told. So please wait till tomorrow evening and listen to the remaining talk."
Next day, I continued my talk." The desire to live one more day as per the Vedas is called "Sat." But we also wish that the extra day should be spent happily - this is the second desire, called "Ananda." When one attains permanent bliss, no one would wish to die, including the lady I met yesterday, who wished to commit suicide!" It is a different matter that I never met the young girl after that!
The third fundamental desire is to gain as much knowledge as possible during one's lifetime.  Just for fun, tell someone "This is an important secret. I will reveal it to you tomorrow!" - she/he will not be able to wait till the next day to find out what that secret is! We are not happy being ignorant. This, the Vedas refer to as "Chit." The Vedas call them together as "Sat-Chit-Ananda."
Sat, Chit and Ananda - are the three desires that we seek, Not knowing this basic truth, we squander our lives in search of trivialities.