Object-level View All and Modify All versus View All Data
Key Takeaway
"View All Records" and "Modify All Records" override sharing settings for one object, while "View All Data" and "Modify All Data" override them for every object in the org. The object-level permissions can be better alternatives, because they open up only the object that needs it.
Sharing settings normally decide which records a user can see. Salesforce has two kinds of permissions that skip those settings. The object-level permissions, View All Records and Modify All Records, skip them for one object. View All Data and Modify All Data skip them for every object in the org. Because they skip sharing, these permissions decide who can reach records that the sharing model would otherwise hide.
Object permissions and sharing
Object permissions set a user's base access to the records of an object. "Read", "Create", "Edit" and "Delete" respect sharing. A user with only those permissions still sees only the records that the sharing model opens to them.
The object-level View All and Modify All permissions appear as View All Records and Modify All Records in an object's permission settings. Unlike Read, Create, Edit and Delete, these two override sharing for that object. You enable them in a permission set or a profile.