The document discusses the evolution of English for Specific Purposes (ESP) through three main phases: 1) expanding demand for English to suit particular needs, 2) developments in linguistics, and 3) educational psychology. It describes approaches such as register analysis, discourse analysis, target situation analysis, and a learning-centered approach that place learner needs at the center of course design. ESP analysis and teaching materials have shifted focus from sentence-level grammar to discourse patterns and organizational structures in texts.