Brenda Bentz lays out some of the benefits of table partitioning in SQL Server:
Table partitioning in MS SQL Server is an advanced option that breaks a table into logically smaller chunk (partition) and then stores each chuck to a multiple filegroups. Each chuck can be accessed and maintained separately. Partitioning is not visible to users; it behaves like one logical table to the end user. Partitioning was introduced in SQL 2005 as an Enterprise edition feature but starting with SQL 2016 SP1 it is available on all the editions.
Table partitioning can work to improve performance in specific circumstances, though you’ll definitely want to do a lot of testing before rolling it out. H/T Amanda White.