Poetic or literary directional pronoun; not used in modern everyday speech.
What you see over there is an old tower.
Dated second-person pronoun; can sound archaic or formal. In modern Japanese, あなた or other pronouns are preferred.
What is your name?
Standard kana spelling; the word is usually written in kana.
Rare kanji form; mainly encountered in older texts.
Derived from そ (that) + な (possessive particle) + た (direction/person). The exact historical development is uncertain, but it originally indicated direction and later extended to second-person reference.