Usually these teams hand work off to each other as it finished one phase and enters the next. In Scrum, the team must be able to do all the work to create vertical slices of working functionality every sprint, including design, development, testing and integration. Therefore, we need a team that is skilled at all those tasks.
Additionally, the team should have the following characteristics:
- Self-Organizing: Team members self-organize to determine the best way to accomplish the goal
- Cross functionally diverse and sufficient: Development team members should have the necessary skills to get the job done
- T-Shaped skills: Team members have deep skills in their specialty, but have the ability to work outside core specialty area
- Musketeer attitude (all for one and one for all)
- High bandwidth communication: Valuable information is communicated quickly and efficiently with minimal overhead
- Right sized: Scrum favors small teams (7+/-2)
- Focused and committed: Each team member is engaged, concentrating on and devoting their full attention to the teams goal
- Works at sustainable pace: Minimal overtime
- Long-lived: Keep teams together as long as it is economically feasible to do so
Feature teams vs Component teams
A feature team is a cross functional and cross component team that can pull features from the backlog and and complete them.
A component team, on the other hand, focuses on the development of a component or subsystem that can be used to create only part of an end-customer feature. Component teams are sometimes referred to as asset or subsystem teams. On these teams, all members likely report to the same functional manager and might operate as a shared, centralized resource to other teams.
Scrum favors feature teams because with component teams you run the risk of competing priorities leading to late work. Also, the hand-offs from one team to the next gets you back into a waterfall-like way of managing your work.
Generally speaking, you want to have teams composed of all the skills necessary to take the backlog item from concept to completion