Laser-foil /thin film interaction results the blow-off plasma, which is applied for tabletop ion accelerators, production of high energy density matter, high-resolution charged-particle radiography, tumor therapy, isotope generation for positron emission tomography, fast ignition of fusion cores, plasma diagnostics etc. Therefore this book is devoted to the experimental and theoretical study on characterization of laser-blow-off (LBO) plasma of multi-component target which is formed by Nd: YAG laser. During the characterization of LBO plume, oscillations in LBO are observed. Oscillations and its amplitude depend on axial position, laser fluence, ambient gas pressure, electric field and magnetic field. Moreover spectral analysis suggests that an acoustic wave is also present in the LBO plasma plume. This study reveals that neutral density gradient and its equilibration are responsible for the oscillations in LBO plasmas.