Efimov physics refers to universal properties displayed by 3-body systems with a large scattering length. These properties are characterized by a discrete scaling behavior in the 3-body scattering amplitude. For example, an infinite series of 3-body bound states exists and the ratio of binding energies of two successive states is 515 in the limit of infinite scattering length. In the beginning of this talk universal aspects in 2-body and 3-body systems will be reviewed and examples from nuclear physics and atomic physics will be provided. The EFT with contact interactions will be discussed as an excellent tool to explore the universality. Finally, two recent studies on Efimov physics in cold atomic systems, $^{133}$Cs and $^{6}$Li, will be presented as examples of universality in systems of ultracold atoms.