Simple design and innovation choices can have a profound impact over time, especially when it comes to inventing something wholly new. Below we take a look at two of the most influential tech inventions of the past 100 years and chart the course of their evolution through time to the present day. Video Slot Machine All modern slot machines descend from a machine known as the Liberty Bell, developed by German inventor and San Francisco resident Charles Fey in the 1890s. If you want to read more about Fey’s slot machine there are comprehensive resources online that detail his process