What is a Vendor? Do I need to enter Vendors? PPS v4.0.27

What is a Vendor? Do I need to enter Vendors? PPS v4.0.27

If you're buying and repacking finished goods products, you'll note the vendor when create case labels. Vendors allows you to use a drop down. If you're buying finished goods, enter your vendors here. 

You can find the Vendors page under Settings > Manage Data > Vendors.
Manage Vendors in the Settings dropdown

Vendor dropdown when creating case labels