The umbrella term agile software development refers to software development methods and practices that provide solutions through the collaboration between self-organizing and cross-functional teams.

Agile methods of software development promote:

• Disciplined project management.
• Leadership philosophies that encourage teamwork, self-organization, and accountability.
• Engineering best practices that make an allowance for the rapid delivery of high-quality software.
• A business approach that aligns their customer needs with their company goals.

Any development process that aligns its methodology with the Agile Manifesto is agile development.

The Agile Manifesto

In February 2001, seventeen independent-minded software practitioners came together to coined The Agile Manifesto. This agile software development proclamation highlights key values and principles that programmers should abide by when creating agile software.

4 Values of the Agile Manifesto

• Instead of focusing primarily on processes and tools, programmers should give more attention to individuals and interactions.
• Working software is valued more than comprehensive documentation of the development process.
• Contract negotiation is less vital than customer collaboration.
• Instead of strictly following a plan, programmers should respond to any occurring change.

• Principles of the Agile Manifesto

1. Satisfying the customer through early and continuous delivery of valuable software.
2. Welcoming changing requirements, even late in development.
3. Delivering working software as frequently as possible and in a shorter timescale.
4. Business people and developers must work together daily throughout the project.
5. The building of projects around motivated individuals.
6. The most efficient and effective method of conveying information to and within the development team is face-to-face conversation.
7. The primary measure of progress is working software.
8. Agile processes promote sustainable development.
9. Continuous attention to technical excellence and good design enhances agility.
10. Simplicity — the art of maximizing the amount of work not done — is essential.
11. The best architectures, requirements, and designs emerge from self-organizing teams.
12. At regular intervals, the team reflects on becoming more effective, then tunes and adjusts its behavior accordingly.

Agile Methodologies

When it comes to adherence to these values and principles of the manifesto, the Scrum and XP methods are the two most common methods.

1. Scrum

This is a project management framework that puts more emphasis on iterative progress, teamwork, and accountability.

1. Extreme Programming (XP)

The XP software development framework aims to improve software quality and responsiveness to changing customer requirements.  It works towards producing high-quality software and quality of life for team members.

Agile works by giving prominence to delivering working software iteratively and incrementally instead of building rigid requirements through big, upfront planning. Each phase of the software development project is allocated a time period (sprint) in which the task should be completed. The task is considered as completed once the allocated time period lapses.

The Agile method process helps programming teams adequately provide quick and unpredictable responses to any feedback they may receive on the project. This process creates opportunities for software programmers to assess a project’s direction during the development cycle.