What is Rhetorical Structure Theory

As the number of electronic text documents is increasing so is the need for an automatic text summarizer. The summary can be extractive, compression, or abstractive. In the former, the more important sentences are retained, more or less in their original structure, while the second one involves reducing the length of each sentence. For the latter, it requires a fusion of multiple sentences and/or paraphrasing. This chapter focuses on the abstractive text summarization (ATS) of a single text document. The study explores what ATS is. Additionally, the literature of the field of ATS is investigated. Different datasets and evaluation techniques used in assessing the summarizers are discussed. The fact is that ATS is much more challenging than its extractive counterpart, and as such, there are a few works in this area for all the languages.