Peperoncino is the generic Italian name for hot chili peppers, specifically some regional cultivars of the species Capsicum annuum and C. frutescens . The sweet pepper is called peperone in Italian. Like most peppers, the fruit is green or yellowish-green when young, and ripens to a red color.
In the United States, peperoncini are usually pickled, comparatively mild – most often the variety known in Italy as friggitelli, a fairly sweet cultivar of C. annuum – and commonly used (whole, sliced, or chopped) as a condiment on sandwiches, in salads, and in Italian-style or other Mediterranean-inspired dishes.