Not long ago I paid 60+ dollars to buy SQL Server Developer Edition from Microsoft Store. Since end of March 2016, you can get it for free. That's very generous. It is a free download but you may have to sign-in to Visual Studio Dev Essentials before you can download SQL Server 2014 Developer Edition. It is assumed that you have a licensed Windows 10 or Windows Server.
SQL Server Developer edition has all the capabilities of the Enterprise Edition, however it is only for development and testing. Of course you can do BI on it. You may not run a business with it.
In Microsoft's own language,
"Visual Studio Dev Essentials is Microsoft’s most comprehensive free developer program ever, with everything you need to build and deploy your app on any platform, including state-of-the-art tools, the power of the cloud, training, and support."
This is great stuff. If you are serious you will not let go of this opportunity.
Go this URL to download SQL Server 2014 Developer Edition with Service Pack 1 (x86) or (x64)
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