This work takes us through the literature on applications of genetic programming to problems of natural language
processing. The purpose of natural language processing is to allow us to communicate with computers in natural
language. Among the problems addressed in the area is, for example, the extraction of information, which draws
relevant data from unstructured texts written in natural language. There are also domains of application of
particular relevance because of the difficulty in dealing with the corresponding documents, such as opinion
mining in social networks, or because of the need for high precision in the information extracted, such as the
biomedical domain. There have been proposals to apply genetic programming techniques in several of these areas.
This tour allows us to observe the potential—not yet fully exploited—of such applications. We also review some
cases in which genetic programming can provide information that is absent from other approaches, revealing its
ability to provide easy to interpret results, in form of programs or functions. Finally, we identify some
important challenges in the area.