When accessing a network drive over a network, i.e.
Why do I need to use the '$', is this just a syntax thing?
It indicates a hidden share, so that anyone on the network is not able to just browse to the share they need to know the specific name.
The dollar sign means that the share is an administrative share. These shares are created for the system to use, not for you.
Best practice is to create a separate share for the drive itself (or the folders within it), and share it the proper way. Leave the administrative share alone, and use the other share.
You should probably also disable the administrative share. This is to prevent someone from logging into your system. Instead, make sure you provision security around the new share properly to secure your system.