What is Metaprogramming?

Metaprogramming is the writing of computer programs that write or manipulate other programs (or themselves) as their data, or that do part of the work at compile time that would otherwise be done at runtime. In many cases, this allows programmers to get more done in the same amount of time as they would take to write all the code manually, or it gives programs greater flexibility to efficiently handle new situations without recompilation. (via Wikipedia)

The following tutorial lists all the methods from the Ruby core that are useful for metaprogramming as well as demonstrates common usage scenarios you will find helpful to get started. In conclution, an example is presented showing how to develop a dynamic database class like ActiveRecord which automatically generates classes for database tables and populates each model class with getters and setters for its fields.