The article discusses different types of grammar and learning algorithms used in grammatical inference. It explains basic grammar definitions, including Backus-Naur form and the Chomsky hierarchy. Various grammar representations like context-free grammar and regular grammar are covered. The article also explains different learning algorithms and compares their strengths and weaknesses. Overall, the article provides a detailed review of approaches for grammatical inference, classifying them based on various factors and presenting the analysis in a tabulated form for easy reference.