Usually authors write introductions for their books, although they know that not many readers will read it. Despite this, authors insist on writing an introduction and no publisher will publish a book without one. I would like to inform my dear readers that I have spent almost all of the first quarter of my life in a village in the Nile Delta, 65 km north of Cairo. The everyday scenery there was the beautiful green landscape dissected with canals full of running water. All of these were bordered with the huge sycamore, mulberry and acacia trees. The desert was something unknown to me at that time, except for the very basic information given in geography books, which explained that the desert is a place without water or cultiva­ tion. Some of my ideas about the desert came to me from the stories in the history of Islam and the desert lands where Islam originated. My real attraction to the desert developed in the last year of my under­ graduate studies. This was during the field courses in Ecology (Prof. A.M.