How to tell what version of SQL Server you are running?

1. One simple way to do this is to run SELECT @@version

SELECT @@VERSION 

Result:

Microsoft SQL Server 2017 (RTM-CU6) (KB4101464) - 14.0.3025.34 (X64)  

Apr  9 2018 18:00:41  

Copyright (C) 2017 Microsoft Corporation  

Standard Edition (64-bit) on Windows Server 2016 Standard 10.0 <X64> (Build 14393: ) (Hypervisor)