It's a group of developers, QAs, Project Managers, and BAs who work on the project together. Such complex team guarantees comprehensive work on the project:
- BA  communicates with clients and defines problems, needs, or areas to improve as well as turns clients needs into tasks
- Project Manager managing the developing process
- Developers ensure flawless developing process and quality
- QAs role is to find all the bugs and drawbacks to fix them and deploy the best possible version of the product