The calculus of differential forms has been applied to electromagnetic field theory in several papers and texts, some of which are cited in the references. Differential forms are underused in applied electromagnetic research. Differential forms represent unique visual appliance with graphical apprehension of electromagnetic fields. We study the calculus of differential forms and other fundamental principle of electromagnetic field theory. We hope to show in this paper that differential forms make Maxwell’s laws and some of their basic applications more intuitive and are a natural and powerful research tool in applied electromagnetics. Dhaka Univ. J. Sci. 67(1): 1-4, 2019 (January)