The shallow water models describe water flow in rivers, lakes and shallow seas. They are used to study many physical phenomena of interest, such as, modeling environmental effects, commercial activities on fisheries and coastal wildlife, remediation of contaminated bays and estuaries for the purposes of improving water quality. However, without any simplifications are very difficult to solve. These assumptions, with respect to several physical aspects are the general source of uncertainty within the modeling process. In this work, we get the derivation of shallow water models for steady and transient phenomena, required assumptions and resulting equations.