The fundamental unit in Scrum is the team. The team is the engine that works to provide a solution in the form of a product. The use of the word team becomes a little redundant in Scrum so the language was modified in 2007 to make a distinction between Scrum Team and team. Before the 2007 the word team was used for both cases and this created confusion. Stakeholders form the context in which the Scrum Team exists. Usually there is someone special in the Stakeholder group we call the Business Owner who asked the team to form and consigned resources to the Product Owner to get the job done.
A Scrum team is made up of the team, the Scrum Master and Product Owner. A scrum team has all of the skills necessary to produce a meaningful increment of work each sprint. There is a balance of power and responsibility across the roles of ScrumMaster Product Owner and team.
Team is typically focused on providing innovative solutions. Can=>What=>How shall we build this?
Scrum Master is concerned with health of the team. Are we a well formed team?
Product Owner is focused on direction of the product. Where to next?
Please note this is but, an introduction to the terms. A full understanding takes reading, training and applied effort to really understand the balance achieved with the Scrum Development Method.