\begin{definition}
\begin{itemize}
 \item 
Si le triangle $OIJ$ est rectangle en $O$, le repère  $(O;I,J)$ est dit \MotDefinition[repère orthogonal]{orthogonal}{}.
\item Si le triangle $OIJ$ est isocèle  en $O$, le repère  $(O;I,J)$ est dit \MotDefinition[repère orthonormé]{normé}{}. 
\item Si le triangle $OIJ$ est isocèle et rectangle en $O$, il est dit \MotDefinition[repère orthonormal]{orthonormal}{} ou \MotDefinition[repère orthonormé]{orthonormé}{}.
\end{itemize}

\parbox{0.3\textwidth}{
Repère orthogonal

\begin{tikzpicture}[general, xscale=0.5, yscale=0.25]
\draw [quadrillage, xstep=1,ystep=1] (-2.5,-5) grid (2.5,5);
\axeOI{-2.5}{2.5}
\axeOJ{-5}{5}
\draw (0,0) node[below left] {$O$};
\end{tikzpicture}
}\hfill\parbox{0.3\textwidth}{

Repère normé

\begin{tikzpicture}[general, scale=0.5]
\draw[quadrillage] (0,0)--(5,0);
\draw[quadrillage] (0,0.87)--(5,0.87);
\draw[quadrillage] (0,1.74)--(5,1.74);
\draw[quadrillage] (0,2.61)--(5,2.61);
\draw[quadrillage] (0,3.48)--(5,3.48);
\draw[quadrillage] (0,4.35)--(5,4.35);
\draw[quadrillage] (0,3.48)--(0.875,5);
\draw[quadrillage] (0,1.74)--(1.875,5);
\draw[quadrillage] (0,0)--(2.875,5);
\draw[quadrillage] (2,0)--(4.875,5);
\draw[quadrillage] (3,0)--(5,3.48);
\draw[quadrillage] (4,0)--(5,1.74);
\draw[axe] (0,1.74)--(5,1.74);
\draw[axe] (1,0)--(3.875,5);
 \draw (1.74,1.74) node[below left] {$O$};
 \draw  (3,1.74) node {{\boldmath $+$}};
 \draw (2.5,2.61) node {{\boldmath $-$}};
 \draw (2.5,2.61) node[left] {J};
 \draw  (3,1.74)node[below] {I};
 \end{tikzpicture}

}\hfill\parbox{0.3\textwidth}{

Repère orthonormé

\begin{tikzpicture}[general, scale=0.25]
\draw [quadrillage] (-5,-5) grid (5,5);
\axeOI{-5}{5}
\axeOJ{-5}{5}
\draw (0,0) node[below left] {$O$};
\end{tikzpicture}}
\end{definition}
