Contributions to our understanding of sea fog from early 20th century to the present have been reviewed. Although emphasis is placed on observations and conceptual models of fog off the California coast, an effort is made to present a more wide-spectrum view of the subject. The celebrated work of English geophysicist G. I. Taylor, conducted in response to the Titanic disaster, assumes a central role in this history. The work of other English scientists, especially those who sought to understand the haar, is given a prominent place in the essay. In the United States, stimulus for research on sea fog stemmed from issues related to commercial and military aviation safety. In this regard, the work of Byers, Petterssen, and Leipper is reviewed. Advances in our understanding of the mechanisms of sea fog formation that have accrued as the result of numerical experiments are summarized. The essay ends by viewing the prospects for advances in our understanding of sea fog in light of earlier work.