Desire is merely one emotion that we feel frequently or constantly on our Journeys and it tends to be a push or pull situation.  We either want something (pull) or we don't want something (push).  Usually we would refer to this as Desire and Aversion but in both cases it is either a Desire to have or a Desire to not have.  It can be difficult to relate to our Desires, especially if our Ego is running the show, we will want to pull towards all the things and activities that we like and push away all the things and activities that we don't like.  Desires can be very useful on our Journey of inner discovery as they can highlight patterns that we have developed over the years since we came into this world.  The most common Desire could be the one of Happiness, due to the misconception of what Happiness is, it is all too easy to pull towards ourselves all of the comforts in life that will give us a false sense of Happiness and push away everything that represents the discomforts that will prevent us from experiencing Happiness.  One we understand more the true definition of Happiness we will know that there are many discomforts that will contribute to our Happiness and hopefully help to lead us away from the constant Desire for comforts. 

In the story of Ramayana, it is Sita's Desire that lead her towards the forest, away from protection and allowed her to be captured.  Rama needed to overcome all of his fears and ask for help from the Gods to rescue her.

Desire is a great paradox, something that we yern for but will actually hold us back on our Journey.  As with Attachment, it does not mean that we must lead a monsatic lifestyle it merely means that we need to have enough Discernment to know what our Desires are, when we are experiencing them and how to not let them hold us back - we need to be aware enough to take the next best step(s).