What is the difference between Agile and Waterfall development models

Waterfall Development Model

Definition

Originally proposed by W.W. Royce in 1970 as a software development model, waterfall development is an older approach to computer software development.

Phases

Requirements Analysis: Detailed analysis and evaluation of the requirements to form a requirements analysis document;

Design: Technical evaluation, planning time nodes, the formation of technical documents as well as time planning;

Development: According to the time plan, development, each phase to complete a certain content;

Testing: After the completion of development, testing, modification if there are problems. Testing: After development is complete, testing is performed, and if there are problems, modifications are made until it is ready to use;

Features

The most typical anticipatory approach, which strictly follows a pre-planned sequence of steps for requirements analysis, design, coding, integration, testing, and maintenance.

Agile development

Definition

A new approach to software development that has been gaining widespread attention since the 1990s, and is a software development capability that responds to rapidly changing requirements.

Features

Emphasis is placed on close collaboration between a team of programmers and business experts, face-to-face communication (which is considered more effective than written documentation), frequent delivery of new software releases, compact and self-organizing teams, methods of writing code and organizing teams that are well adapted to changes in requirements, and a greater focus on the role of people in software development.

Working style

Working as a whole;

Working on short iteration cycles;

Delivering something per iteration; ?

Focusing on business priorities;

Checking and adjusting;

Waterfall development model

Advantages:

1. Steps are clear and unambiguous;

2. Documentation is complete, and it can be used as a reference during the development process;

Disadvantages:

1. Waterfall development is developed from industry, and is not suitable for the computer software development;

2, the development cycle is long, spend a lot of time to write documents, time and labor;

3, the customer can only see the results of the completion of the entire project, which can lead to trust issues;

4, risky, in the process of development does not understand the final result, while not being able to adapt to change;

Agile development mode

Advantages:

1, fast iteration, short development cycle;

2, no longer spend a lot of time to write documents, but people face-to-face communication, and only write some of the necessary documents;

3, the division of labor in detail, the output of the results of the output every day, the customer can be seen, will trust the project team;

4, communication, easy to find the problem, and can stimulate the team to work. Problems, at the same time can stimulate the team's collaboration, struggle;

Disadvantages:

1, trust between people is a very important part, but this is more difficult to complete, members of the technical team may be a big difference in technical skills, but also compete with each other, or members of the project team have some reservations, unwilling to communicate in this way;

2, the team in development

2. During the development period, the team has many tasks, high pressure, and needs to be "excited" all the time, which is generally difficult to do.