Explanation of differences between corvettes, frigates, destroyers and cruisers (as recorded from a Quora discussion):

Minesweeper: it's job to to find and remove mines to clear a harbor or other restricted waters for maritime access and egress. There can also be minelayers which do the opposite.

Corvettes: They were smaller sailing vessels used for coastal commerce and and defense. They were fast and maneuverable. Today some navies use these in a similar way but they are not sail powered. The US Navy has similar vessels called Littoral Combat Ships.

Now to Frigates, Destroyers and Cruisers. These range from smallest to largest in the same order. Cruisers tend to be picket ships specializing in air defense. They also have Tomahawk missiles that can be launched against land or sea targets.

Destoyers are smaller than Cruisers and used to be more for submarine warfare and then became a smaller version of a cruisers with much the same mission. Frigates were the smallest. They were primarlily anti-submarine platforms.