  This work first gives the global existence and optimal decay rates of
solutions to the classical Timoshenko system on the framework of Besov spaces.
Due to the \textit{non-symmetric} dissipation, the general theory for
dissipative hyperbolic systems ([30]) can not be applied to the Timoshenko
system directly. In the case of equal wave speeds, we construct global
solutions to the Cauchy problem pertaining to data in the spatially Besov
spaces. Furthermore, the dissipative structure enables us to give a new decay
framework which pays less attention on the traditional spectral analysis.
Consequently, the optimal decay estimates of solution and its derivatives of
fractional order are shown by time-weighted energy approaches in terms of
low-frequency and high-frequency decompositions. As a by-product, the usual
decay estimate of $L^{1}(\mathbb{R})$-$L^{2}(\mathbb{R})$ type is also shown.
