Below is the documentation here and here . Especially this detail:
RealmList is used to model a one-to-many relationship in a RealmObject.
RealmResults are always the result of a database query. RealmList can be used inside a RealmObject to define a one-to-many relationship (RealmResults cannot).
Also this part:
RealmList has two modes: managed and unmanaged. In managed mode, all objects are stored inside Realm; in unmanaged mode, it works like a regular ArrayList.
RealmList may not be managed, so act like a normal ArrayList, while RealmResults is the "window" into the database. Objects are not copied or placed in RealmResults, they only refer to them.
In short, RealmResults are always the result of a database query, while RealmLists do not have to be.
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