Agile is an iterative approach to software delivery that builds software incrementally from the start instead of delivering it all at once near the end. There are some prerequisites for effective agile adoption, including prioritizing individuals and interactions over processes and tools, ensuring it is a team effort across departments, and understanding that the goal is more aligned and less wasted work rather than just faster delivery. Adopting agile properly requires self-organizing teams rather than forced organization from management, but many organizations struggle with this transformation. The most important aspects of agile are self-organizing teams and a focus on results rather than processes.