What 鋼 means
鋼 means steel, an iron-carbon alloy.
In Chinese, 鋼鐵 means iron and steel; in Japanese, 鋼 is はがね (hagane) alone and コウ (kō) in compounds.
Where does 鋼 come from?
The Chinese character dictionary Yupian, compiled in 535–551, defines 鋼 as refined iron. The philosophical text Liezi uses it for a sword blade. Archaeology records Eastern Zhou iron industries, including weapons production in the state of Chu, before that written record.
Literal for materials; literary when it stands for toughness.
Use 鋼 in Japanese or Traditional Chinese; Simplified Chinese uses 钢.
What it means when someone sends it to you
2 readingsQuestions people ask
1Why does 鋼 show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type 鋼
鋼\92FCCodes and encoding1 code points
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.