Mark Knoller, a veteran CBS News White House correspondent, passed away at 73. Known for his meticulous record-keeping of presidential activities spanning eight administrations, he was considered a legend by colleagues. Knoller, who had diabetes, diligently documented presidential speeches, travel, and even golf outings, becoming an invaluable resource for reporters and historians. Starting his career at WNEW Radio, he joined CBS in 1988 and later transitioned to Twitter, maintaining a strong online presence. His dedication and encyclopedic knowledge earned him the title of unofficial presidential historian and statistician.

Prepared by Emily Rhodes and reviewed by editorial team.