In a traditional software development life cycle, we process in a forward direction and we can not make changes in between the process. So, seventeen software developers came with a manifesto of 4 values and 12 principles to improve this method. You can check this out on the agile manifesto website. If your software development life cycle follows these values and principles then the agile methodology is implemented.
These are the four values from Agile manifesto:
1. Individuals and interactions are more important than processes and tools because everyone thinks differently and needs to value the inputs of the other team members.
2. Working software over comprehensive documentation since you need efficient and good software at the end.
3. Customer collaboration is important than the negotiation of contract because customer satisfaction is more important.
4. Responding to the change over a fixed plan because the client does know what he wants at the starting and we need to change the plan in the middle of the project.
If you want to learn Agile methodology, you can take up the Agile Training course by intellipaat.
You can have a look at this video What is an agile methodology for detailed explanation:
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