The document discusses 3D coordinate systems and vectors. It defines: 1) The distance formula in 3D space between two points (x1,y1,z1) and (x2,y2,z2) as the square root of (x2-x1)2 + (y2-y1)2 + (z2-z1)2. 2) Vectors as quantities that have both magnitude and direction. It shows examples of vector addition and subtraction using the triangle and parallelogram laws. 3) Key properties of vectors including that vector addition is commutative and distributive over vector addition, scalar multiplication distributes over vector addition, and vectors