There are main reasons common to the emergence of all ESP :
1. The demands of a Brave New World
The end of the Second World War in 1945 heralded an age of enormous expansion and unprecedented in scientific, technical and economic activity on an international scale. This expansion created a world unified and dominated by technology and commerce. This development has been accelerated through the Oil Crises in the early 1970s, which resulted in a massive flow of funds and Western expertise into the oil-rich countries. Created a lack of time and money needed for cost effective courses with clearly defined goals.
The general effect of this development was to pressure on the profession of teaching language to deliver the goods required. Whereas English it now became subject to the wishes, needs and demands of people other than language teachers. English become responsible to the scrutiny of the wider world and the traditional and purposes free through the landscape of the English language seemed no longer appropriate in the harsher realities of the market place.
2. A Revolution in Linguistics
Linguistics aims to describe the rules of English usage, that is the grammar. In English language teaching this Led to the view that there are important differences between the English of commerce and that of engineer. The idea was easy : if language varies from one situation of use to another, it should be possible to determine the specific situations and then make these features the basis of the learners’ course. A lot of the work at this time was in the area of English for Science and technology (EST). The gained ground that English needed by a particular group of learners could be identified by analyzing the linguistic characteristics of their specialist area of work or study.
3. Focus of the Learner
New developments in educational psychology also contributed to the rise of ESP, by Through the central importance of the learners and their attitude to learning (e.g. Rodgers,1969). The Learners have different needs and interest, which would have an important influence or their motivation to learn and therefore on the activeness of their learning. This provided support to the development of courses in the which relevance to the learners need and interests was paramount.