Sitecore consists of three major products:
Sitecore Experience Manager (XM)
Sitecore Experience Platform (XP)
Sitecore Experience Commerce (XC)
Each of the Sitecore components contains a number of logical entities that together with a number of cloud services form the entire functionality of the Sitecore platform.
The roles depicted here are logical and do not represent physical or virtual servers, database servers, or search engines. Some logical roles can be combined into single physical entities within a topology.
Sitecore Experience Manager
XM refers to the web content management (WCM) core of the Sitecore Experience Platform. XM encompasses the features involved in the creation, management, personalization, and publishing of content. (The features available depend on which type of XM installation you have.) XM consists of the subset of the logical roles:
Sitecore Experience Platform
XP combines XM with the marketing and customer intelligence features offered by xConnect and xDB. xConnect and xDB introduce a number of additional server roles and storage mechanisms.
xConnect is the name given to the set of services that sit in between xDB and any trusted client, device, or interface that wants to collect and search experience data over HTTPS.
xDB is the name given to the collection of services and storage roles that store and process experience data. Clients that are external to xDB - such as a Content Management server - must use xConnect to read and write xDB data.
The following diagram lists the logical roles that are added by XP:
XP roles extend the content management, personalization, and delivery features of the XM with features that enable cross channel experiences, customer and business insights, collect actionable customer information and provide context when shaping the experience for customers.
The following diagram lists every logical role included in XP:
Sitecore Experience Commerce
Sitecore Experience Commerce (XC) is a fully integrated, feature rich commerce solution. Deployed on top of Sitecore Experience Platform, Sitecore XC combines content management, personalization, marketing, customer intelligence and data with advanced commerce functionality in a single, powerful enterprise-level solution.
The following diagram shows the roles that Sitecore Experience Commerce includes:
Single and multitenancy
Sitecore XC supports both single and multitenancy out of the box.
With a single tenancy setup, you have a single website – or storefront – served by the Content Delivery role.
In the following diagram, the storefront makes calls to the Commerce Engine, accessing the entities and business logic configured for it.
With a multitenancy setup, a Content Delivery role can house multiple storefront sites and the Commerce Engine can host multiple entity and business logic configurations.
In other words, you can have a single instance of a Content Delivery role and Commerce engine role, hosting numerous storefront sites, each with completely tailored functionality.