SSRS

SQL Server Reporting Services

Do not install SSRS on the SQL Server machine unless you have a good reason. 

A good reason would be something like... you can't get budget to license a separate machine and you are licensed per individual virtual machine rather than per physical server with software assurance (aka "Maximum Virtualisation"). i.e. it's better to take a performance hit than run improperly licensed software.

Install on a dedicated machine if you can.

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