The agile manifesto has been created and published by 17 experienced software developers in 2001. It defines four key values and twelve principles.
The four values are:
Individuals and interactions over processes and tools
Self-organisation and motivation are very important for teams to work efficiently.
Working software over comprehensive documentation
Focus on delivering working software instead of documentation papers.
Customer collaboration over contract negotiation
It is ok to implement the feature different as it was written down. Most of the time it is hard to imagine it before it was made - IKIWISI (I’ll know it when I see it.)
Responding to change over following a plan
Respond to changes as fast as you can to gain advantage over others. Continuous development is essential for that.
The values on the right side are important, but the focus should be on the values on the left side, because they are more critical for success.