Starting with SOLIDWORKS 2016, two levels of SOLIDWORKS PDM are available: SOLIDWORKS PDM Standard and SOLIDWORKS PDM Professional.
SOLIDWORKS PDM Standard is a new product based on SOLIDWORKS Enterprise PDM. It is included with SOLIDWORKS Professional and SOLIDWORKS Premium.
SOLIDWORKS PDM Professional is the name of the product previously called SOLIDWORKS Enterprise PDM. It is available as a separately purchased product.