what type of food did mcdonald's initially specialize in

McDonald's initially specialized in hamburgers when it first streamlined its operations in 1948. The McDonald brothers originally opened McDonald's Bar-B- Que in 1940, but they eventually focused on a simplified menu centered on hamburgers, cheeseburgers, french fries, milkshakes, and soft drinks as part of their Speedee Service System. This pivot to hamburgers became the core of their fast-food business model and their early success.