Definition:Latin Square/Example/Order 4

Example of Latin Square of order $4$
This is an example of a Latin square of order $4$:


 * $\begin{array}

{|cccc|} \hline a & b & c & d \\ c & d & a & b \\ d & c & b & a \\ b & a & d & c \\ \hline \end{array}$