A long-time Miso question

Hello JB! :D This is my first forum I create, and it's a question that has been perplexing my little mind for quite awhile. :] I am wondering three things:
1) What is the differences between the types of miso *red, white, etc.?
2) What kind of miso is best to use for miso soup?
3) Is there a way to make the condensed miso (like I've seen for other soups) to pack into a bento?
Thank you very much for your time minna,

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