What's new in SQL Server version x

A frequent question I get is what the new stuff is in some version of SQL Server. And, sure, Microsoft has a very exhaustive "what's new" section for each version of SQL Server. The purpose of this page is to list all news on one page. Focus is on the SQL-engine. 

SQL Server 2017 (https://docs.microsoft.com/en-us/sql/sql-server/what-s-new-in-sql-server-2017)
  • Whitelisting of assemblies along with sp_configure option clr strict security
  • Resumable online index rebuild.
  • IDENTITY_CACHE allowing for non-gaps in identity on hard shutdown, but with a performance penalty).
  • Adaptive Query Processing:
    • Adaptive joins.
    • Memory grant feedback.
    • Interleaved execution for MSTVF.
  • Automatic tuning.
  • Graph tables.
  • Setup allow for 256 GB tempdb files.
  • Column modified_extent_page_count in sys.dm_db_file_space_usage tracks differential changes in each database file.
  • SELECT INTO has option to specify filegroup.
  • Availability groups:
    • Cross database transactions.
    • Clusterless.
    • Minimum Replica Commit Availability Groups.
    • Linux, including mixed environments.
  • New DMVs
    • sys.dm_db_log_stats exposes summary
    • sys.dm_tran_version_store_space_usage
    • sys.dm_db_log_info
    • sys.dm_db_stats_histogram
    • sys.dm_os_host_info
  • Database Engine Tuning Advisor allow specify Query Store for workload
  • In-memory
    • Computed columns
    • JSON
    • CROSS APPLY
  • Functions
    • New
      • CONCAT_WS
      • TRANSLATE
      • TRIM
    • WITHIN GROUP for STRING_AGG