This week, Penguin Books celebrated the 80th anniversary of its paperbacks. Allen Lane launched the inexpensive line of ten books on July 30, 1935, and they were an instant hit. Ever since then, readers have been devouring the tomes with the little flightless bird on the binding.

While instantly recognizable today, the poised penguin has gone through a series of changes over the course of its 80 years. Lane always knew he wanted to use the image of an animal, but it wasn’t until 1935 when his secretary suggested the penguin as a “dignified, but flippant” name for the new company that the idea took flight. A young office hand named Edward Young was sent off to the London Zoo that day to sketch penguins.

Allen opted for non-illustrated jacket designs with color used to indicate genre—a move that made the Penguin logo even more distinguishable. The look of the bird changed frequently over the next decade (as you can see, some early versions were quite squiggly), and many times since, with some notable weight losses and gains. It was refreshed as recently as 2003 by Angus Hyland.
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