The katana is the most famous and iconic Japanese sword; the long, curved, one-edged sword that you pretty much never see a fictional samurai without.
Notice the distinctive shape and the fact that it’s almost as sharp as Crono’s hair.
There are a lot of misconceptions about katana, though.
1. All Japanese swords (or all Japanese swords except ones of significanly different length) are katana; nope.
2. Katana have been the traditional Japanese sword since ancient times.
I’ve going to address those two together because the same counterexample works for both; Ame no Murakumo, the sword that Susanoo found after slaying the Orochi, which was later renamed Kusunagi no Tsurugi and became one of the three Japanese Imperial Treasures. This is one of the most famous Japanese swords, and a very old one as well; and as it’s second name says, it’s a tsurugi, not a katana.
The tsurugi is a straight, double-edge sword, and far older than the katana; the katana didn’t become the main Japanese sword until around 1400. And samurai actually originally specialized in bows, not either kind of sword.
3. Katanas are superior to other swords.
Because Japan is relatively poor in iron, the metal wasn’t often wasted on weapons of low quality, so this does have some truth to it statistically speaking, but the idea that the average katana is better than the very best non-Japanese sword is a total myth.
4. Katanas can easily cut through other swords.
Only if the other swords aren’t steel.
But it’s possible to go too far the other way. Someone tried to prove that broadswords were better than katanas by having two smash into each other edge-on and showing the katana break, and people who said “it’s because the broadsword is more of a blunt weapon” were written off as believing too much katana hype…but the thing is they were basically right. When two swords hit each other, they can’t cut each other and are both acting as blunt weapons against each other…and katanas are terrible at being blunt weapons. Katana fighting styles also emphasize evading more than guarding, so there’s no guarantee that the blades would actually clash in a fight involving one.
The katana is a pure slashing weapon. It specializes in sharpness, and in a competition that involved actually cutting things, it would win against a broadsword; it would probably win against anything else made of steel.
And in a competition to see what weapons could break other weapons, or inflict damage through metal armor, a mace would beat any sword.
The most common kinds of European swords, on the other hand, are versatile weapons as opposed to specialized ones. Pretty good at several things, but not the best at anything. Declaring which is better between a generalized weapon and a specialized one is highly subjective.