Kirchhoff Loop and Junction Rules

Kirchhoff's rules are bookkeeping rules for one real circuit, not a second subject pasted on top of circuit ideas. The junction rule says current is conserved where a path splits or recombines, and the loop rule says the algebraic sum of voltage rises and drops around any closed loop is zero.

This module stays intentionally bounded to one outer resistor and one highlighted two-resistor group. In the parallel case, that group gives you one true junction and two branch loops. In the series case, the split disappears and the same current keeps crossing every resistor. That is enough to make loop balance, current conservation, and sign convention feel concrete without turning the page into a general circuit solver.