Two technologies have been proposed for RDF validation based on the notion of shape: Shape Expressions (ShEx) and Shapes Constraint Language (SHACL). The adoption of both languages in different semantic web applications and domains has been gradually increasing since their appearance and they are claiming their space in the semantic web stack. ShEx was designed as a concise, human-readable language for RDF description and validation, while SHACL was designed as an RDF vocabulary that allows to describe constraints on RDF data. Although both have some similarities, they were designed from different perspectives. In this tutorial we will present both ShEx and SHACL using examples, discuss the rationales for their design and compare them. We will also present some tools that are being developed around shapes, as well as some applications like the wikidata entity schema namespace which allows to create an ecosystem of shape expressions to validate wikidata entities.