The study investigates the electron-phonon coupling in high-temperature superconductors using angle-resolved photoemission spectroscopy (ARPES). The researchers examined three families of copper oxide superconductors: Bi2212, Pb-doped Bi2212, Pb-doped Bi2201, and LaSrCuO4 (LSCO). They observed a sudden change in electron velocity at 50-80 meV, which is attributed to coupling with phonons associated with oxygen atom movements. This effect is consistent across different systems and doping levels, suggesting that electron-phonon coupling strongly influences electron dynamics in these materials. The findings rule out alternative explanations such as magnetic mode coupling and support a phonon interpretation, which is further supported by neutron scattering data and temperature dependence analysis. The study highlights the importance of electron-phonon coupling in high-temperature superconductivity and calls for more theoretical work to understand its role.The study investigates the electron-phonon coupling in high-temperature superconductors using angle-resolved photoemission spectroscopy (ARPES). The researchers examined three families of copper oxide superconductors: Bi2212, Pb-doped Bi2212, Pb-doped Bi2201, and LaSrCuO4 (LSCO). They observed a sudden change in electron velocity at 50-80 meV, which is attributed to coupling with phonons associated with oxygen atom movements. This effect is consistent across different systems and doping levels, suggesting that electron-phonon coupling strongly influences electron dynamics in these materials. The findings rule out alternative explanations such as magnetic mode coupling and support a phonon interpretation, which is further supported by neutron scattering data and temperature dependence analysis. The study highlights the importance of electron-phonon coupling in high-temperature superconductivity and calls for more theoretical work to understand its role.