What is the difference between a dashboard and a scorecard?

A scorecard measures performance against goals and typically display in graphic indicator to visually display the overall success and failure. It is based on key performance indicators(KPIS).

Scorecard sample

But a dashboard is a container for various types of reports, and provide high level of interactivity.

Dashboard sample

More at: http://office.microsoft.com/en-us/sharepoint-server-help/what-is-the-difference-between-a-dashboard-and-a-scorecard-HA101772797.aspx