What are an agile manifesto and its principle?

The Agile Manifesto is a declarative statement of principles and values that describes a series of values and beliefs followed by various organizations. It centers on the idea that collaboration, communication, transparency, and creativity are key to ensuring success in software development. It's principle emphasizes teamwork, responsibility for one's work as well as one's fellow team members, an iterative approach to development based on fast feedback from users and clients. At its core it is designed to optimize processes by focusing on continuous improvement through short-term plans with frequent adaptation in response to change.