Coming from the こそあど言葉（ことば） family of words, こう, そう, ああ, or どう may be used with the verb 言（い）う to form an expression which literally means ‘in the way of (A)’. (A) being ‘this’ これ, ‘that’ それ, ‘that over there’ あれ, or ‘what’ どれ (in questions). As with all pre-noun adjectival words, this expression will be used directly before a noun.

• こういう映画（えいが）は始（はじ）めてみる。
  This is my first time watching a movie like this. (This ‘kind’ of movie)
• そういう人（ひと）は嫌（きら）い。
  I don't like people like that. (That ‘kind’ of people)
• ああいう車（くるま）に乗（の）ってみたい。
  I want to try to drive a car like that one. (That ‘kind’ of car)
• あなたはどういう音楽（おんがく）を聴（き）きますか？
  What kind of music do you listen to?

Although こう, そう, ああ, and どう share a relationship with これ, それ, あれ, and どれ, they are their own individual words, which each have a meaning similar to ‘as such’. These words are all 副詞（ふくし） (adverbs) when used by themselves.