  The primary aim of this paper is to characterize the uniformly locally
univalent harmonic mappings in the unit disk. Then, we obtain sharp distortion,
growth and covering theorems for one parameter family ${\mathcal
B}_{H}(\lambda)$ of uniformly locally univalent harmonic mappings. Finally, we
show that the subclass of $k$-quasiconformal harmonic mappings in ${\mathcal
B}_{H}(\lambda)$ and the class ${\mathcal B}_{H}(\lambda)$ are contained in the
Hardy space of a specific exponent depending on the $\lambda$, respectively,
and we also discuss the growth of coefficients for harmonic mappings in
${\mathcal B}_{H}(\lambda)$.
