what is Agile methodology?

Agile methodology: An approach of Software development:
Agile offers new methodological approaches, which works on iterations and always welcome the new changes during the development. Agile approach believe on chunks known as sprint, where both team and client can review their final product in a two weeks time.In this approach customer is involved in development phase, so that they can see real working software in such a small time and they can decide the next steps without loosing their lots of time and money.
Agile is a Methodological approach in respond to the problem faced by traditional software development approaches such as Waterfall or Sequential during the software development.Traditional Model have lots of disadvantage such as poor management of requirement, putting huge effort during the planning phase.

In Agile, project manager can deliver the best product in terms of higher prioritize features.
Agile has few important methods such as
Scrum
XP(Xtreme Programming)
Adaptive Software Development
Dynamic System development Method
However Agile also have some cons like other methodologies, in my view Agile methodology does not have proper documentations, reason being the changes require quick responses, apart from that
before going ahead agile methodology should be understand properly in case of misunderstanding of the agile methodology may create a wrong directions.

Agile methodology having lots of advantages such as
It reduce the number of defects in the final product.
Reduce software cost and time
Due to it's flexible nature agile methodology always welcomes last minute changes
Increase business efficiency.
Each team members become responsible.