Optomechanically induced transparency (OMIT) is a phenomenon analogous to electromagnetically induced transparency (EIT) in optomechanical systems. In EIT, a control laser creates a narrow spectral window for a probe laser, enabling light slowing and storage. OMIT achieves this in a cavity optomechanical system operating in the resolved sideband regime. A control laser tuned to the lower motional sideband induces a dipole-like interaction between optical and mechanical degrees of freedom. When a two-photon resonance condition is met, destructive interference of excitation pathways creates a transparency window for the probe field. The control laser's power determines the window's width and depth. OMIT enables light delay, slowing, and storage in mechanical excitations, with tunable optical and mechanical properties in micro- and nano-optomechanical platforms. OMIT has potential applications in photonic quantum memory and optical buffering. It was first observed in atomic gases, but recent experiments in optomechanical systems show that mechanical motion can be controlled by optical fields. This effect has been used for optomechanical laser cooling, amplification, and coupling. OMIT is a strict optomechanical analog of EIT, offering advantages such as no reliance on natural resonances and applicability to inaccessible wavelengths like near-infrared. A single optomechanical element can achieve unity contrast, similar to cavity QED in atomic systems. The experiment used toroidal whispering-gallery-mode microresonators, which feature low effective mass and high coupling. These resonators allow reaching the resolved-sideband regime, enabling OMIT. The system was operated at cryogenic temperatures with a Helium-3 buffer gas cryostat to minimize thermal motion and eliminate thermo-optical nonlinearities. A low-noise Ti:sapphire laser was used for OMIT experiments, with its linewidth stabilized to a reference cavity. The mechanical motion was detected using a balanced homodyne scheme, measuring the phase quadrature of the cavity output. The mechanical resonance frequency, quality factor, and effective mass were extracted. The probe transmission was analyzed by inducing a frequency-tunable modulation sideband on the control laser. The transmission window width and depth were determined by the control laser's power. The experiment confirmed the presence of OMIT, with a sharp transparency window when the two-photon resonance condition was met. The results show that OMIT can achieve high probe power transmission, up to 81%, indicating high contrast. The width of the transparency window was found to be wider than 500 kHz. The study highlights the potential of OMIT for applications in fundamental and applied studies, including all-optical switches and light storage. The ability to dynamically tune group delay in optomechanical systems could enable efficient pulse propagation through arrays. The findings demonstrate the feasibility of OMIT in optomechanical systems, with implications for future optical and mechanical technologies.Optomechanically induced transparency (OMIT) is a phenomenon analogous to electromagnetically induced transparency (EIT) in optomechanical systems. In EIT, a control laser creates a narrow spectral window for a probe laser, enabling light slowing and storage. OMIT achieves this in a cavity optomechanical system operating in the resolved sideband regime. A control laser tuned to the lower motional sideband induces a dipole-like interaction between optical and mechanical degrees of freedom. When a two-photon resonance condition is met, destructive interference of excitation pathways creates a transparency window for the probe field. The control laser's power determines the window's width and depth. OMIT enables light delay, slowing, and storage in mechanical excitations, with tunable optical and mechanical properties in micro- and nano-optomechanical platforms. OMIT has potential applications in photonic quantum memory and optical buffering. It was first observed in atomic gases, but recent experiments in optomechanical systems show that mechanical motion can be controlled by optical fields. This effect has been used for optomechanical laser cooling, amplification, and coupling. OMIT is a strict optomechanical analog of EIT, offering advantages such as no reliance on natural resonances and applicability to inaccessible wavelengths like near-infrared. A single optomechanical element can achieve unity contrast, similar to cavity QED in atomic systems. The experiment used toroidal whispering-gallery-mode microresonators, which feature low effective mass and high coupling. These resonators allow reaching the resolved-sideband regime, enabling OMIT. The system was operated at cryogenic temperatures with a Helium-3 buffer gas cryostat to minimize thermal motion and eliminate thermo-optical nonlinearities. A low-noise Ti:sapphire laser was used for OMIT experiments, with its linewidth stabilized to a reference cavity. The mechanical motion was detected using a balanced homodyne scheme, measuring the phase quadrature of the cavity output. The mechanical resonance frequency, quality factor, and effective mass were extracted. The probe transmission was analyzed by inducing a frequency-tunable modulation sideband on the control laser. The transmission window width and depth were determined by the control laser's power. The experiment confirmed the presence of OMIT, with a sharp transparency window when the two-photon resonance condition was met. The results show that OMIT can achieve high probe power transmission, up to 81%, indicating high contrast. The width of the transparency window was found to be wider than 500 kHz. The study highlights the potential of OMIT for applications in fundamental and applied studies, including all-optical switches and light storage. The ability to dynamically tune group delay in optomechanical systems could enable efficient pulse propagation through arrays. The findings demonstrate the feasibility of OMIT in optomechanical systems, with implications for future optical and mechanical technologies.