Please kindly introduce the Agile Methodology

Agile is not a new concept and can be traced back to 1957, in the early 1990’s a number of software development methodologies were being used by software teams. The Agile Development Methodology four values:

Individuals and interactions over processes and tools
Working software over comprehensive documentation
Customer collaboration over contract negotiation
Responding to change over following a plan
Performance is measured by customers at the end of the iteration. The lessons learned in each iteration are captured in retrospectives and used in future iterations. In this way, the products are constantly improved and the process for developing them also improved.

2.