Also, a type of surface combatant, generally of less than 500 tons displacement (as a ship larger than this is a corvette or frigate, not a missile boat), armed, as the name implies, with various types of missiles. Most missile boats currently in service are of Russian and French design, and as such are typically armed with the SS-N-2C Styx, SS-N-22 Sunburn, SS-N-25 Switchblade (Harpoonski) or SS-N-27 Klub Russian anti-ship missiles, or the French Exocet. The Italian Teseo is also seen occasionally, as is the American Harpoon and the Chinese C-802. Israel also produces their own missile boats, armed with Harpoon and Gabriel III. (Though the larger Sa'ar V class which made the news recently is more properly termed a corvette).
Missile boats aren't very durable, and they have short ranges, and poor survivability for their crews once in combat. However, they are exceedingly inexpensive (often less than fifty million US dollars), and have considerable firepower for their size. Both Israel and Syria have had some significant success with missile boat warfare. The counter to this, however, would be Iran, whose missile boats were quickly smashed by the US Navy during Operation Praying Mantis, and Iraq, which fared little better, their forces being quickly demolished by British attack helicopters and Sea Skua missiles.
Newer trends in naval warfare seem to be veering away from the typical SSM-armed FIAC, however, in favor of very light speedboats armed with guns or one-shot missiles and suicide bombs, backed up by a few light corvettes with some air defenses. Nevertheless, the threat posed by FIACs is taken seriously by all the world's major navies (Consisting mainly of the USA, UK, Canada, Australia, Japan, China and Russia). Of these, only the USA, Canada, Japan and Russia have units well-suited to fending off numerous FIACs, and even then, usually with missiles that cost a significant fraction of the price of their targets.