Typically displacing around 2000 tons and carrying a crew of 750, the Second rates carried 32-pounder guns on the gundeck, with 18 pdrs instead of 24 pdrs on the middle deck, and 12 pdrs on the upper deck (rather than 18 or 24 prds on First rates). Both First and Second rates carried lighter guns or carronades on their forecastles and quarterdecks.
The three-decker Second-rate was mainly a British type, and was not built by other European navies to any great degree. Apart from its unhandiness, in terms of sheer firepower it was matched or even over matched by the 80 and 74-gun two-decker Third-rates used by the French and Spanish navies instead. The additional deck did, however, give the second-rate an advantage in close combat, and it had the further tactical advantage of sometimes being mistaken by the enemy for a first-rate which could possibly make enemy commanders reluctant to press an attack.
The term second-rate has since passed into general usage as an adjective used to mean of suboptimal quality, or an unacceptable replacement for something that is first-rate.