Thanks to their unique physicochemical properties (e.g., surface plasmon resonance), noble metal nanoparticles are at the cornerstone of nanotechnology. Silver triangular nanoprisms are presented here as an ideal playground to introduce students to nanochemistry concepts such as the formation of shape-controlled nanostructures. Not only a reliable and straightforward protocol for the synthesis of silver nanoprisms is described, but also their formation is explained in terms of basic oxidation--reduction mechanisms; their peculiar optical properties are compared with those displayed by silver nanospheres and discussed in relation to their shape.