The paper discusses the implications of the latest CTEQ6.6 parton distribution functions (PDFs) for collider observables, particularly at the Fermilab Tevatron and CERN Large Hadron Collider (LHC). The CTEQ6.6 PDFs, obtained through a global analysis of hard scattering data in the framework of general-mass perturbative QCD, are used to study theoretical predictions and their uncertainties for significant processes. The paper highlights the previously observed increase in predicted cross sections for W and Z boson production in the general-mass scheme compared to the zero-mass scheme. A novel method to constrain PDF uncertainties in LHC observables by exploiting PDF-induced correlations with benchmark standard model cross sections is introduced. This method shows that the top-antitop (t̄t) cross section can serve as a standard candle observable for LHC processes dominated by initial-state gluon scattering. Precise measurements of t̄t cross sections would reduce PDF uncertainties in predictions for single-top quark and Higgs boson production in the standard model and minimal supersymmetric standard model. The paper also explores the impact of heavy-quark mass effects, the treatment of strange quark distributions, and the role of intrinsic charm contributions on PDF predictions and correlations.The paper discusses the implications of the latest CTEQ6.6 parton distribution functions (PDFs) for collider observables, particularly at the Fermilab Tevatron and CERN Large Hadron Collider (LHC). The CTEQ6.6 PDFs, obtained through a global analysis of hard scattering data in the framework of general-mass perturbative QCD, are used to study theoretical predictions and their uncertainties for significant processes. The paper highlights the previously observed increase in predicted cross sections for W and Z boson production in the general-mass scheme compared to the zero-mass scheme. A novel method to constrain PDF uncertainties in LHC observables by exploiting PDF-induced correlations with benchmark standard model cross sections is introduced. This method shows that the top-antitop (t̄t) cross section can serve as a standard candle observable for LHC processes dominated by initial-state gluon scattering. Precise measurements of t̄t cross sections would reduce PDF uncertainties in predictions for single-top quark and Higgs boson production in the standard model and minimal supersymmetric standard model. The paper also explores the impact of heavy-quark mass effects, the treatment of strange quark distributions, and the role of intrinsic charm contributions on PDF predictions and correlations.