The basic difference of a List/Committee vs an Email List is where it displays in the Info Hub. 

When adding or creating a new list, you have two options to select: Add List/Committee and Add Email List.

The only thing that controls where a list/committee displays in the Info Hub is the Primary Category assigned to the list/committee. By default, there are four list/committee categories set up in GrowthZone: 

1. Staff: this will set the list up as a list/committee, and will allow the Community Integration option to appear.
2. Board Members: this will set the list up as a list/committee, and will allow the Community Integration option to appear.
3. Email Lists: this will set the list up as an email list, and the Community Integration option will NOT be available for this list.
4. Member Engagement: this will set the list up as a list/committee, and will allow the Community Integration option to appear

You can set up as many List/Committee categories as you like in your system; you may need to experiment with your custom list/committee categories to find the correct one for your system (or select one of the known default list/committee categories above instead).

Lists created using any category EXCEPT "Email List" will display in the "My Info" section of the Info Hub, under a "Lists/Committees" panel:

Lists created using the "Email List" category will display under the "My Subscriptions" area IF the "Users can see List in My Info or My Subscriptions" option is enabled. If "Users Can Join" is also enabled, members can subscribe or unsubscribe from the list via the Info Hub by enabling and disabling the check box.

Other than that, a List/Committee list and an Email List list behave the same in all other ways; they can be used to send emails, as a workflow source, etc. If you enable the "Allow External Use" option, you can even publish a list of either type to your website.