History, need definition, philosophy, principles, approaches and objectives of extension education, Present status of extension and rural Development programmes. Teaching/learning process, Extension Teaching Methods, classification and selection of teaching methods. Nature and importance of communication. Key elements of communication. Models of communication, process, feedback and problems in communication. Importance of audiovisual aids in extension education. Classification, planning and selection of A.V.Aids. Identification of rural leaders, their characteristics, roles and functions in rural development, training of rural leaders. Definition of groups, natural types, principles of working with groups and their mobilization. Need, principles and steps of programme planning. Evaluation of extension programmes. Diffusion of innovations and categories of farmers. Conceptual orientation about different terms, like- PRA, RRA, IVLP/TAR, ATMA, ATIC, PTD etc.