Generics allow functions and classes to work with multiple data types. They avoid function overloading by using type parameters within angle brackets (<>) to specify the data type. Generic functions and classes can work with any compatible type, like a Display function working with strings, integers, or doubles. Delegates are similar to classes that refer to functions. They come in single-cast and multi-cast varieties, with the latter referring to multiple functions. Delegates are created using the delegate keyword and instantiated by assigning a function and invoked like regular functions.