Lee Schulman described pedagogical content knowledge as a special blend of content knowledge and pedagogical strategies that a teacher uses in the teaching of a particular content area.
Researches on the nature of pedagogical content knowledge have described it as a highly content, context and person specific knowledge. It is a knowledge that results from years of practice and reflection on practice and it involves taking a right pedagogical decision at a right time and for the right purpose.
Thus pedagogical content knowledge does not only involve the in depth knowledge of the content area but it also involves a correct use of reasoning as to the selection of a proper strategy to teach that content to the student while keeping in view the specific students requirements in terms of their learning needs .
This way of describing pedagogical content knowledge makes it so specific that it is believed that it cannot be delivered to the teachers through instruction alone. Some of the researches suggested that owing to its specific nature, PCK can only develop through practice.
Although this way of characterizing PCK identifies it as a strictly specific type of knowledge, yet to be a type of knowledge there must be some kind of universal element in it. For the knowledge of a specific situation in which there is no element of generality cannot be called knowledge proper. Knowledge basically is an interaction between subject and object and hence bears the characteristics of both.
The situation can be viewed in the light of Aristotle's distinction between a man of experience and the artist. Art lies in knowing the reason for one's prticular choice in a particular situation, where as