In this thesis we consider the branching ratios and CP asymmetry in the B meson decays into two pseudoscalar mesons in the generalized factorization approximation. We also investigate the possible effects of the enhanced chromomagnetic interaction b → sg on these exclusive B meson decays that was suggested as a possible solution to the semileptonic branching ratio of B mesons, the missing charm puzzle and the large B → η``+ $X_s$. We finds that such enhanced b → sg interaction degrades the agreement between the data and the model predictions for B meson decays into two light mesons in the generalized factorization approximation.
We also suggest a new method to extract the weak phaseγ by exploiting B → $DK^{(*)}$ decay modes that are not Cabibbo suppressed, using the isospin relations, and ignoring the annihilation diagram as usual. Assuming 3×$10_8$ B $\bar{B}$ pair at B factories, one can determineγ with 3-σ accuracy for 80。≤γ≤150。 using B → DK modes and for 50。≤γ≤170。 using B → $DK^*$ modes.