The first credit card, issued in 1950, was Diner's Club.

Diner's Club was indeed founded in 1950 and introduced an early charge card, but the claim that it was 'the first credit card' is problematic. Earlier charge/credit systems existed, including Western Union's 'metal money' in the 1920s and various merchant-specific credit programs. However, Diner's Club is often credited as the first multi-merchant charge card that worked across multiple establishments.