Show that the function

$f(x)=\{\begin{array}{cc}\frac{e^{\frac{1}{x}}-e^{-\frac{1}{x}}}{e^{\frac{1}{x}}+e^{-\frac{1}{x}}},& x0\\ 0,& x=0\end{array}$

is discontinuous at $x=0.$ Also mention the type of discontinuity.