When a vector is used to define a hyperplane in this way it shall be denoted by , while if it is designating a point we will use . They are referred to as "point coordinates" or "hyperplane coordinates" respectively (in the important two-dimensional case, hyperplane coordinates are called "line coordinates"). Some authors distinguish how a vector is to be interpreted by writing hyperplane coordinates as horizontal (row) vectors while point coordinates are written as vertical (column) vectors. Thus, if is a column vector we would have while . In terms of the usual dot product, . Since is a field, the dot product is symmetrical, meaning .