A good summary, but for one imortant detail: In UTF-16, some code points (laying on the so-called "astral planes", ie not on the "basic multilingual plane") take 32 bits.
The Emoji, for example, lie on the first higher plane: 🍒🎄🐰🚴. Firefox and Safari display them properly, Chrome doesn't, no idea for IE and Opera.
UCS-2 is a strict 16-bit encoding (a subset of UTF-16), and it cannot represent all characters.
It is the encoding used by JavaScript, which can be problematic when double width characters are used. For example, `"🐙🐚🐛🐜🐝🐞🐟".length` is 14 even though there are only seven characters, and you could slice that string in the middle of a character.
The Emoji, for example, lie on the first higher plane: 🍒🎄🐰🚴. Firefox and Safari display them properly, Chrome doesn't, no idea for IE and Opera.
UCS-2 is a strict 16-bit encoding (a subset of UTF-16), and it cannot represent all characters.
It is the encoding used by JavaScript, which can be problematic when double width characters are used. For example, `"🐙🐚🐛🐜🐝🐞🐟".length` is 14 even though there are only seven characters, and you could slice that string in the middle of a character.