What is keyword extraction?
Keyword extraction is the retrieval of keywords or key phrases from text documents. They are selected among phrases in the text document and characterise the document’s topic. In this article, I summarise the most commonly used methods that automatically extract keywords.
Methods that automatically extract keywords from the documents use heuristics to select the most used and significant words or phrases from the text document. I classify keyword extraction methods in the field named natural language processing, which is an important field in machine learning and artificial intelligence.
Keyword extractors are used to extract words (keywords) or groups of two or more words that create a phrase (key phrases).