You may not stop to think too much about it, but almost every T-shirt design that has been popular over the past few decades is either born from popular culture or inspires a generation to take up a cause. For example the yellow smiley face design may seem ingrained into our subconscious, but did you know that it was designed in about 10 minutes in the early 1960’s by Harvey Ball for the State Mutual Life Assurance company of Worcester, Massachusetts? Although originally meant to cheer up employees, years later the face was slapped on products everywhere and turned into a fad that made $50 million in sales in a year and a half. Nowadays, we see versions of the “Keep Calm and Carry On” slogan on T-shirts as people adjust the words to fit a certain message. However, by using the same design, layout and fonts these shirts instantly remind us of the original. You can learn more about T-shirt trends of the past few decades by reading through the following infographic.