Heat Transfer is a course that is offered to some engineering students such as Mechanical Engineers and Chemical Engineers. These series of Heat Transfer courses are designed for undergraduate students in Mechanical Engineering who are interested in learning the subject in depth and aim for an A. Also, graduates who are preparing for their FEor PEexam can immensely benefit from these lectures. In this course, the students will gain complete confidence in their ability to apply the first law of thermodynamics to open/closed systems for steady/unsteady processes in order to calculate heat transfer rate. Also, the misconceptions about Cp and Cv and how to use them to calculate heat transfer rate will be addressed. Then conduction (Fourier's Law), convection (Newton's Law of Cooling), and radiation (Stefan-Boltzmann Law) are introduced and for every heat transfer mechanism, examples are provided. For radiation to surroundings, the net radiation and Kirchhoff's law will be discussed. Parameters such as reflectivity, absoptivity, emissivity, and transmissivity will be introduced. The course includes about 6 hours and half of lectures and examples. This lays a very solid foundation before steady conduction and thermal resistance network, unsteady conduction, external and internal convection, and heat exchangers are introduced in the next parts of this course.