We give definitions , notes on usage , and examples . Today we talk about innovation . Innovation is an improved way of doing something . Innovation can lead to change that makes for a better product or idea . Sometimes innovation involves a new , physical invention . Some innovations are revolutionary . Innovation brings us to the world of bread and today's expression : the best thing since sliced bread . The best thing since sliced bread describes a new , excellent thing that makes a great improvement to something . For example , the new map and direction app on my smartphone is the best thing since sliced bread ! Now , when driving I find my destinations easily and only get lost when my phone dies . But where does this expression come from ? Well , for many years , bread has been a main part of meals for many people around the world . Most bread comes in a long form , called a loaf . A bread loaf travels well . You can buy a loaf of bread , stick in your bag , and make it home without the bread getting damaged . And on the way , you can break off a piece of bread for a little snack . But when making a sandwich , you need two slices of bread of the same thickness . If you had to cut them yourself , that may not happen . One may be thicker than the other -- one of life's little annoyances . Well , that changed in the late 1920s . An inventor in the United States brought an innovation to the world of bread . Otto Frederick Rohwedder invented the bread slicer . Later , a small machine to toast the bread was invented . The slices fit neatly into the toaster . Toasters can be found in homes across the U.S . and other countries . Sliced bread became even more popular . People love bread and Rohwedder's creation revolutionized the bread industry . So , being described as the best thing since sliced bread is high praise , indeed . Here is another example . So , what do you think of the chief's new policy on paid leave ? It's the best thing since sliced bread ! I'm going to use the extra vacation time to visit friends in Paris . Please note : People also use the expression as an insult . Let's say you know someone who thinks very highly of herself . she thinks she can do no wrong . You don't agree . You could say , “She thinks she's the best thing since sliced bread .”