<p>The origin of chemical elements in the Universe is strictly related to stars, since during the Big Bang, only light elements (H, D, He, and Li) formed, while all the elements from carbon to uranium and beyond were synthesised inside stars, so that we can say to be <i>children of the stars</i>. The chemical composition of the solar system is the results of billion years of nuclear processing inside stars. In this review, we will describe how to obtain constraints on the origin of chemical elements by studying the abundances of such elements measured in stars and gas. In particular, we will describe how detailed models of galactic chemical evolution can unveil the origin of elements, and in particular, we will discuss the biogenic elements, namely those which are parts of many living organisms, such as H, C, N, O, Mg, Ca, S, and Fe. The elements produced by either slow or rapid neutron capture on heavy seed will be also discussed.</p>