This Instructional Activity is a part of the Lesson 2, Unit 2, Grade 8. Before explaining explicitly what translation along a vector is, review the question that started the discussion. Then, draw a vector, and demonstrate how to translate along the chosen vector to map the lower left figure to the upper right figure. Consider showing several examples of vectors that can be used instead of just one. A vector is a directed line segment,that is, it is a segment with a direction given by connecting one of its endpoint (called the initial point or starting point) to the other endpoint (called the terminal point or simply the endpoint). It is often represented as an "arrow" with a "tail" and a "tip.".