Red Solo cups have become an iconic symbol at American parties. The Solo Cup Company originally produced paper cups, but the red plastic cup was introduced in the 1970s and became an instant hit ...

The glossy, fire-engine-red plastic cup—better known as the Solo cup—is an unmistakable symbol of American party culture. It’s shown up on virtually every college campus and long ago cemented its ...

The true purpose of the horizontal lines on the sides of the original Solo cups have been an enduring mystery, but no more.