This is a pretty generic question so I'll try to give you a high level overview here. After reviewing the high level overview I'd suggest posting more specific questions in each of the solution specific communities so you can get more specific answers from experts in those areas.
Adobe Analytics | Adobe Audience Manager | Adobe Target | Adobe Experience Cloud Audiences
For a high level overview, you can pass in almost any data you'd like from your website/app into Adobe Analytics via a marketing tag. That data can then be shared through our Experience Cloud Audiences functionality to other Experience Cloud solutions. A similar process can be done via Audience Manager or the Audience Library interface using data from your CMS or data that you may have purchased from a data provider. The Adobe Experience Cloud can then help you match various traits against a customer's profile and action on that information using solutions like Adobe Target to personalized the customer's experience based on the information available within their customer profile.
New visitors are a bit tricky because we typically are limited on what traits might be known about the visitor. For more information on this, I'd definitely recommend posting a more specific question on one of our more specific communities.
-Jantzen