Used to ask about the nature, type, or manner of something. Often followed by な to modify a noun, or used adverbially with に.
What kind of book is that?
How should I go to the station?
Kanji form; encountered in formal writing but uncommon in everyday use.
Alternate kanji form; very rare and may be considered archaic or literary.
Compound of interrogative prefix どの (which) and よう (様, 'appearance, manner'). The kanji spellings reflect the components but are rarely used.