The Economist calls itself a newspaper because its founder referred to it as a "weekly paper" that was to be published every Saturday, and up until very recently, its format and appearance was in keeping with those of a newspaper. Its coverage is also newspaper-like.
As of the 2015 version of its masthead, The Economist literally calls itself "the newspaper," a term that is connected to its long history as much as to its current function. When it was first established in the 19th century, the publication called itself a journal that covered issues involving politics, commerce, trade and agriculture. The journal was published completely in black and white until 1959, the first appearance of the red logo. The first color cover was published in 1971, and the publication did not use full color in all its pages until 2001.
Although The Economist no longer looks like a newspaper, the broad range of issues it covers makes it unlike magazines, which often narrow coverage to much more specified areas. The lack of bylines in The Economist is also a characteristic that may seem strange to modern readers who are used to seeing a byline in most stories, no matter how brief. But this tradition is in keeping with newspaper practices until recently, in which leaders appeared without a byline.