Rollback Segement vs Redo log

Hi, there

Can some one explain the functional differences between rollback segment and redo log in a brief description?

I am still confused by theses two things and got more confused when I read concept manual from Oracle.

Redo and rollback? sounds like the same. thanks in advance for your feedback

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John Chan
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RTE Asset Management (aka. Rightime Econometrics, Inc.)
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