Scrum is an agile framework for creating complex software products.
A product owner begins a product backlog list of features and functionality for a new system. The backlog is continuously prioritized by the product owner. A team gathers during a Sprint Planning Meeting to decide which features from the top of the backlog (in prioritized order) they can complete within a sprint (usually one to four weeks, commonly two). This meeting finalizes what the team is committed to completing within the sprint.
The sprint begins. Every day, the team meets briefly to communicate progress and request help with technical issues, product questions, or anything else that is slowing their work down.
At the end of the sprint, the team and anyone else that wishes to attend gather at a Sprint Review Meeting. The team presents the new features completed within the sprint that are potentially shippable working software in order to gather feedback from executives, managers, customers, and the product owner. Before planning the next sprint, the team has a Sprint Retrospective Meeting to gather feedback from just their peers, to improve the state of communication, collaboration, and cohesion of the group.
The cycle repeats itself. A new sprint planning meeting begins and more features are selected for the next sprint. The team gets to work again. The product owner adjusts the product backlog, making new plans. Everyone always inspecting, always improving, always adapting.
Throughout the entire process, the Scrum Master facilitates the meetings, encourages agile practices and makes sure the team stays focused and the product owner is working on the product backlog.