i googled it for you....basically the same stuff they told me when i learned about it in school
from wikipedia: 
http://en.wikipedia.org/wiki/Agile_software_development
Individuals and Interactions – in agile development, self-organization and motivation are important, as are interactions like co-location and pair programming.
Working software – working software will be more useful and welcome than just presenting documents to clients in meetings.
Customer collaboration – requirements cannot be fully collected at the beginning of the software development cycle, therefore continuous customer or stakeholder involvement is very important.
Responding to change – agile development is focused on quick responses to change and continuous development.[6]
Twelve principles underlie the Agile Manifesto, including:[7]
    * Customer satisfaction by rapid delivery of useful software
    * Welcome changing requirements, even late in development
    * Working software is delivered frequently (weeks rather than months)
    * Working software is the principal measure of progress
    * Sustainable development, able to maintain a constant pace
    * Close, daily co-operation between business people and developers
    * Face-to-face conversation is the best form of communication (co-location)
    * Projects are built around motivated individuals, who should be trusted
    * Continuous attention to technical excellence and good design
    * Simplicity
    * Self-organizing teams
    * Regular adaptation to changing circumstances