To make correct analogies between different branches of physics is an effective way to understand physics as a whole. By studying the concept of electric charge in electricity, the idea of thermal charge was introduced in thermodynamics. Entropy was then defined as quantity of thermal charge. Accordingly, it is now a physical quantity that is more understandable. Based on this, further comprehensive analogies were made between thermodynamics and electricity including the continuity and driving forces of electric current and entropy current, their relations with energy current as well as the entropy generated in both currents. Consequently, the analogies highlight the similarities and commonalities in the physical processes in thermodynamics and electricity, signify the harmony within the objective world, but also reveal the unique characteristics and differences between the two. Thus, we are allowed to understand entropy more in depth.