Thanks for your question. There is a significant difference between DTM and Analytics and they are intended for different things. DTM is designed to help you manage and tailor your customer site experiences through a number of methods. First the very easy management of the tags necessary to deploy site tools and capability such as Adobe Analytic or Target, but also other third party vendors ad code, survey tools, tracking code etc. Second DTM is a business rules and logic mechanism to create personalized experiences based on user history, behaviour, visiting patterns etc.
There is a good intro video here on our help hub for DTM if you want to check it out. http://helpx.adobe.com/marketing-cloud/dynamic-tag-management.html
If you have other questions, please let us know.
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