そこ or それ?
When to use which? Please help
JackRabbitEgan already gave a good break down, but the short answer is that you would use そこ to indicate "there" or "that place" and you would use それ to say "that" or "that item/person/thing".
These words are handy for identifying nearby places or objects when asking questions or providing descriptions.
それ is a word equivalent to 'that', where the thing is closer to the listener than the speaker, あれ is similar accept it means that when the object is close to neither the listener nor the speaker.
そこ, and あそこ both mean 'there' as in a place そこ being closer to the listener, while あそこ is close to neither listener nor speaker.
so それ何ですか would be, what is that? while そこにあります would mean, it's there (by you).
Remember that there is no equivalent word for 'it' in Japanese as it's baked into the demonstrative words ここ、そこ、あそこ。
Just a tiny note: それ refers to things closer to the listener than the speaker. これ is the one used in the opposite situation.
No no no, the difference between こ れ, そ れ, あ れ and こ こ, そ こ, あ そ こ is that the first group is used "alone" and the second group is ALWAYS accompanied by the name of the thing it designates. これは何ですか。What is that? この傘は誰のですか。 Whose umbrella is that?
That is true for kore and kono. But the original question was asking about kore and koko.
こ こ, そ こ, あ そ こ are for "here" "there" and "over there".
そこ "there", (location), point your finger and say "there", that is そこ それ means "that", if your friend shows you a picture of a game and you say "I wanna buy that", that is それ。They're actually pretty different