Soda tabs are one of those things that it is difficult to imagine life without. Understandably so, since canned beverages have been around since the 1930's. The rise of soda cans came shortly after the success of canned foods, which were first being produced as early as 1915. When canned beverages came along, the cans were more slender and cylinder in shape. They were constructed either of aluminum or steel and were sealed on both ends with a flat top that needed to be opened with a mechanism called a church key. The church key was used to puncture two holes in the top of the can: One opening for drinking, and a small hole on the opposite side to let air in so that the contents would flow out.
The first version of the soda tab was very much like the one we still use today. It was invented by Ermal Fraze, who was inspired to create it after he spent an afternoon at a picnic that was well stocked with cans of beer, but nobody had a churn key to open them! After a few nights of brainstorming he made what he called the Pull Tab. The tab was designed to be pulled and lifted off the surface of the can to expose the drinking area. Since the tab had to be disposed of, people were either dropping them back inside their drink or tossing them on the ground.
The Coors Beer Company found a solution to the mounting litter problem by designing their own tab in the mid 1970's. They made the tops to the drinking opening penetrable, so that they could be pushed down through the can and tucked away underneath the surface. Since it was being pushed in rather than pulled off, they made it without a gripable round ending, and instead provided a raised "blister" to help position the thumb for pushing downwards. This however presented a problem when people started to cut their fingers on the opening's sharp edges, especially if they had a few beers prior to the blunder. In response to the tab's "pressing" safety issue, Coors redesigned it into the modern style soda tab that we use today, which is a combination of the two original styles.