Go to the Sage customer portal customers.sagenorthamerica.com/.../
You will need your user and password.
Click KB and Downloads > Sage Knowledgebase
Click My downloads (at top right)
Select a Sage 100 version (2013 to 2017)
You will find a What's New document for each version

Sage 100 a branding name change only. The product MAS 90 ( now Sage 100 Standard), MAS 200 Client Server (now Sage 100 Advanced) and MAS 200 SQL (now Sage 100 Premium). These newer named products work exactly like their prior associated product. Do not confuse with a totally different product Sage 200 which has nothing to do with prior MAS 200 products.

MAS 200 was originally MAS90 C/S meaning it was the Client Server version meant for a Windows server with MAS90 was a file server version meant for Novell server (remember those). When Sage rebranded MAS 200 because Sage 100 Advanced. If you are on a version known as MAS 200 then you will see a lot of changes in Sage 100 v2017. Lots more functionality