Link combines the directives with a scope and produce a live view. For registering DOM listeners as well as updating the DOM, link function is responsible. After the template is cloned it is executed.Pre-linking function: Pre-linking function is executed before the child elements are linked. It is not considered as the safe way for DOM transformation. Post linking function: Post linking function is executed after the child elements are linked. It is safe to do DOM transformation by post-linking function