In NMR spectroscopy, J coupling is the scalar interaction between nuclei that results in the resonances being represented by multiple lines. When teaching the phenomenon of J coupling, chemistry curricula worldwide, from high-school to graduate programs, suggest that J couplings can be determined from the frequency differences of peaks or lines in the various levels of multiplets following the n+1 rule for 1 H. A common term, peak distance, evolved from the time when spectra were plotted, and a ruler was used to measure the distance between peaks within a multiplet. This distance was then converted into frequency units. The term, (peak) distance, is obsolete and should not be used.