A supernova light curve is of interest, being useful for analysis revealing characteristics of the supernova. The recorded light curve generally begins after the initial brightening since its time cannot be anticipated. The decline rate of Type Ia supernova light curves have been correlated to their brightness, enabling the use of them as standard candles. Some core collapse supernova light curves include a period of very slow decline (termed its plateau), while at a luminosity which has shown a relation with the supernova's ejecta velocity, the latter of which can be measured through the use of spectrography determining radial velocities, which allows these Type II supernova to be used as standard candles as well. Supernovae lightcurves show evolving spectral signatures indicating particular elements/temperatures, and isotopes. Signatures of radioactive isotopes such as 56Ni, 56Co (Cobalt), 60Co, and 44Ti (Titanium), allow reconstruction of nuclear reactions including radioactive decay, and analyzing backward, reveal information about the explosion and the internal conditions of the progenitor star. Kilonova light curves offer analogous analysis, though only a few have been identified.