Roles determine the visibility of data to users and are a key aspect of controlling access to records. They also influence reports, such as the "My Teams" filter. Roles are relevant when your security model (Org-Wide Defaults) is set to private. Users at any given role level can view, edit, and report on all data owned by or shared with users below them in the hierarchy, unless your organization’s sharing model specifies otherwise. For more information about Salesforce Roles, refer to this Salesforce article.

Profiles dictate how users access objects, fields, page layouts, Apex classes, Visualforce pages, and data within the application. They define record privileges, determining what actions users can perform on records provided they have visibility. Profiles also control other system privileges, such as mass email and data export. When creating users, you assign a profile to each one.