[skgoa]

It used to be that these categories had very different roles. Nowadays, NATO defines these categories based on size. Well, technically the water displaced by the hull. The main difference is in how many missiles a given category can carry and how much a ship of that size costs.

Battleships only exist as mothballed reserves. A battleship was one of the largest ships in the fleet with massive guns and super thick armor. It was meant to fight in the major fleet vs. fleet battles. The name stems form "line of battle ship", because these ships were typically arrayed in a line starting back in the late middle ages. When WW2 showed that airplanes and missiles had made big guns and armor redundant, battleships were relegated to being giant anti-air plattforms that escorted the aircraft carriers. No one built any new ones since then, though "missile battleships" were studied for a while.

A massive step down in size are cruisers, who used to be ships that operated independently form the fleet. There are very few of those around nowadays and they tend to be the core of a fleet instead of cruising alone. You will often see them armed with hundreds of anti-ship missiles nowadays.

The next step down are destroyers, which are still fleet escorts (mostly against aircraft, hence Air Warfare Destroyer) in the major navies and have also taken up the role of going on independent operations. This is because smaller navies tend to not have any destroyers or bigger ships, so sending one destroyer armed with say 64 missiles can be sufficient. A destroyer used to be a relatively small ship that had the job of defending the fleet against other small ships like torpedoboats or submarines. The name stems from "torpedoboat destroyer".

The next smaller categories is frigates. These are the most numerous and are the workhorses of modern navies. They do convoy escort, but also defend bigger fleets from submarines. Many navies also send them on independent missions. They will tend to have 16 or 32 missiles, but won't typically have the big anti air radar a destroyer would. "Frigate" was the name used for sailing ships that couldn't stand in the line of battle. I.e. in say 1750 there would be only two categories: line'o'battleships and frigates.

Those categories are the major ocean-going combat ships. There are lots of smaller ships below that and a lot of support ships, too.

[blackflame7000]

It seems you have a lot of knowledge of Naval ships and I was wondering if you could explain the practical difference between a Guided Missile Destroyer like the Arleigh-Burke class vs a Guided Missile Cruiser like the Ticonderoga class?

[skgoa]

The difference was almost entirely the size. The US used to have very few cruisers during the 70ies, but the Soviet Union had a lot of ships that were much smaller than US cruisers, yet designated as cruisers. So the US simply redesignated all large destroyers (i.e. the entire Ticonderoga class) as cruisers, arguing that the larger size enabled them to e taskforce flagships. But the difference in size between the Ticonderogas and the first Burke's (build 15 years after the Ticos IIRC) was only roughly 1000 tons and by now the 3rd generation of Burkes is as large as the Ticos were.