Guided learning - https://powerbi.microsoft.com/en-us/guided-learning/powerbi-learning-0-0-what-is-power-bi/
Concepts and documentation - https://powerbi.microsoft.com/en-us/documentation/powerbi-service-basic-concepts/
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- https://www.lynda.com/Power-BI-tutorials/Power-BI-Pro-Essential-Training/485820-2.html
- https://www.lynda.com/Power-BI-tutorials/Up-Running-Microsoft-Power-BI-Desktop/445425-2.html
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Youtube video - https://www.youtube.com/watch?v=nOaeJ9D_9D4 (there are several more available online for specific topics within powerbi)
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