- As others have pointed out, they are usually three or rarely two or four blocks long, and in terms of addressing someone, they are suffixed by the honorific -씨.
- Korean uses word spacing, which makes it very easy to pick out someone's name.
- Also, for some formal situations, they may be written in Hanja instead.
In Terms of English, note that English actually followed the German Practice of capitilising each Noun for quite a While before They reduced the Capitilised Words Set to Proper Nouns only.
Specifically for East Asian Royalty, there is an extremely complex method of making specific names that are used in certain situations:
- Era names (연호/年號); these are not very distinctive, especially in a long text composed solely of Hanja.
- Temple names (묘호/廟號); quite distinctive, usually ends with 祖 (dynasty founder) or 宗 (all others). King Sejong is an example of the latter.
- Posthumous names (시호/諡號); extremely disctinctive, composed of a long string of Hanja adjectives. The longest ever recorded is for the Empress Dowager Cixi (孝欽慈禧端佑康頤昭豫莊誠壽恭欽獻崇熙配天興聖顯皇后).
There was also a concept of taboo characters, where during the reign of a sovereign, the Hanja of their personal name was not allowed to be written, so the last stroke might be cut off deliberately for that character to remain in use, but I'm not sure how seriously Korea took this taboo. If this does happen, then the character looks extremely weird and distinctive, e.g.

for the Kangxi Emperor.
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