“Salesforce offers a user role hierarchy that you can use to with sharing settings to determine the levels of access that users have to your Salesforce org’s data. Roles within the hierarchy affect access on key components such as records and reports.” (Salesforce Help)
Roles
Roles are assigned to Users within Salesforce. They can resemble Organisational hierarchies but largely determine data access.
Role hierarchy
Users with an assigned role will have to view, edit and report access to all data for roles beneath them in the role hierarchy. For example, a User assigned to a C-Level role will have access to all data owned by roles below them in the hierarchy.
To find out more about Roles and their configuration, head to Create a User Role & Add Roles to the role hierarchy
Roles
Roles closely resemble the Organisational hierarchy but are primarily used to determine Record-level access based on a range of criteria.
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