McDonald's changed its name from McDonald's Famous Barbecue to McDonald's in 1948.
The change followed Richard and Maurice McDonald's decision to close their original barbecue restaurant in San Bernardino, California, and reopen it with a simplified, faster menu. The new operation emphasized hamburgers, cheeseburgers, fries, milkshakes, and counter service rather than a broad barbecue offering.
This rebranding accompanied the introduction of the Speedee Service System, which became an important part of the restaurant's early identity. The brothers did not yet operate the global corporation associated with the modern Golden Arches; that later expansion was driven largely by franchise agent Ray Kroc.
A common mix-up is confusing the 1948 renaming with the founding of McDonald's Corporation in 1955. They were separate milestones: the restaurant adopted the shorter name first, while the corporation was established several years later.