NEON is a Consumer Data Platform, where almost all functionality relates to Individual Consumers. Different platforms use different names, for example Subscribers, Customers, Users, Members, Consumers, People.
In the NEON world these are called Members.

NEON operates equally well as the company's central member database, holding all the CRM and other data about the member, OR as a separate add-on promotion or data platform which only holds a sub-set of members or member information.

NEON does not have a fixed member profile or fixed mandatory attributes. It is entirely up to each organisation to specify as few or as many data "buckets" (Lists) as they like, and data attributes can easily be added, even for individual promotions.
The only Member fields that NEON specifies are:

member FieldDescription
Member IdThis is a generated, unique internal identifier for each member
External IdAn optional unique external identifier which can be used to map the member to the customer's Member database
StateA NEON state which is used by NEON functionality as well as for certain Portal report. The state can be one of:
ACTIVE. The default state
TEMP. The member is temporary but have not yet registered. This enables tracking member activity even before members have signed up or logged in

- DELETED. The member has been "permanently" deleted from NEON. They still remain in the database as an anonymised record since their may be transactional information linked to the Member.
There are a few more states which can be used for reporting purpose. (Note that if other states are required you can simply create your own state field within a Data List)
Opted InThis is a system-wide marketing opt-in setting. Someone who is not opted in should never be marketed to. See Subscription Lists for fine-grained marketing preference control.
Email AddressThis is the email address which NEON will use when sending emails.
See Member Entity configuration for rules around emails
Email StateThis field tells NEON if the email has been verified, if it's bounced etc
Mobile numberThe is the mobile (cell phone) number which NEON will use when sending text messages.
See Member Entity configuration for rules around mobile numbers
Mobile StateThis field tells NEON if the mobile number has been verified, if it's bounced etc
DimensionsThe Dimensions used when the Member was first created. Enables reporting of acquisition by promotion, country etc