What " means
Its full-width shape takes up a whole character slot.
Older Japanese fixed-cell systems gave Japanese characters square cells and Latin text narrower ones. The fullwidth quote aligned punctuation and worked with legacy encodings; Japanese word processors used it in the late 1970s.
Mainland Chinese text commonly sets Western-style quotes fullwidth; Japanese and Traditional Chinese writing commonly use paired corner brackets such as 「」.
Don't confuse it with
2Questions people ask
1Can normalization turn " into ASCII `"`?
Yes. NFKC is a text-cleanup rule that folds width variants, turning it into ASCII `"` and losing the width distinction.
How to type "
"\FF02Codes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.

