  We describe the determination of the strong coupling constant
$\alpha_s(M_Z^2)$ and of the charm-quark mass $m_c(m_c)$ in the $\bar{\rm
MS}$-scheme, based on the QCD analysis of the unpolarized World deep-inelastic
scattering data. At NNLO the values of $\alpha_s(M_Z^2)=0.1134\pm
0.0011(\text{exp})$ and $m_c(m_c)=1.24 \pm 0.03 (\text{exp})\,^{+0.03}_{-0.02}
(\text{scale})\,^{+0.00}_{-0.07} (\text{th})$ are obtained and are compared
with other determinations, also clarifying discrepancies.
