In this book, it has been shown that many of the facets of the stellar jets may be simulated in a pure fluid dynamic experiment, without the need of electromagnetic fields, what is an important issued in astrophysics; some facets of the jets are included the detailed aspects of the head bow shock, its bluntness and the shape of the cocoon as a function of the density ratio and Mach number. This methodology allows giving some insight on the behavior of the free hypersonic jet flows.