To Mayte, my best friend, for her support and encouragement before I worked on this project, even before she knew what was it all about. For the support and encouragement while I worked on it. For the money and time spent in lunchtimes, books, web sites, servers and computers. For unending days of unending weeks and months with no tangible output. For helping me with databases, taking books from libraries and returning them, copying texts and doing everything alone for me, so that I could work more time on the main project. And for her excitement when talking about the changes that this work could bring for the world's future. THANK YOU.

To my parents, for understanding finally how important it was for me to have enough free time to write this.

To my good friends and the others, even to those who are not with me anymore, because every single one of them has given me something which eventually ends in this work.