Because of its relative brightness (mv about 11.8 in quiescence and mv about 8.6 in outburst), SS Cygni is the Dwarf Novae most extensively studied since 1896 (Mattei et al., 1985; Bath and van Paradijs, 1983).
Concerning its long-term behaviour, SS Cygni has short, long and anomalous out-bursts. Correlations between outburst characteristics and periodicities have been studied by van Paradijs (1983), Campbell (1934), and Sterne and Campbell (1934).
SS Cygni, as any cataclysmic variable, also presents rapid variations. Since the discovery of this variability (Warner and Robinson, 1972) many long runs of high-speed photometry have been performed for different Dwarf Novae, both during out-bursts and in quiescence stages. Regarding to SS Cygni we can summarize these variations as: