Hi ,
The Adobe Marketing Cloud (https://marketing.adobe.com ) provides a framework for accessing the different solutions (Adobe Analytics, Social , DTM, Target etc. ) from one place using Adobe ID (An Adobe ID is the user's account for all Adobe solutions. Users create their own Adobe IDs in the process of linking their solution accounts to the Marketing Cloud).
You can link your solution credentials with your Adobe ID. This enables you to log in to all of your solutions ( Adobe Analytics, Adobe DTM, Adobe Target, Social etc ) from one place i.e. Adobe Marketing Cloud.
For example, in Analytics and Social, link (or map) the Company, Username, and Password values to your Adobe ID.
For more information about Organisations & Account Linking , Please see the following link - https://marketing.adobe.com/resources/help/en_US/mcloud/organizations.html
Also , For more information about Adobe Marketing Cloud Core services , Please see the link - https://marketing.adobe.com/resources/help/en_US/mcloud/admin_getting_started.html
Thanks & Regards
Parit Mittal