There are two main types of teleradiology providers: NightHawks and DayHawks. NightHawks provide preliminary radiology reports within 30 minutes for most exams and 10 minutes for strokes, with final reports issued the next morning. DayHawks focus on issuing final reports within 24 hours for most exams and one hour for urgent exams. While NightHawks allow radiologists to read from anywhere, DayHawks require radiologists to be located domestically. The document discusses the differences in services provided, customers, compensation models, and opportunities for collaboration between these two teleradiology models.