Today we are talking about two things that at first seem unrelated -- changing your mind , and shoes . Okay , first shoes . In the summertime , many people around the world wear a kind of casual shoe known as “flip-flops .” They are completely open . So , they keep feet cool in warm weather . They are also good to wear in the shower , at the beach or by a swimming pool – anywhere wet . Word and shoe experts both agree that flip-flops come from Japan . An article in the New York Times explains that after the Second World War ended , Japan increased its production of rubber . Among other things , workers used rubber to make a version of a traditional Japanese sandal , called the zori . Japan exported these rubber zoris all over the world . But the public did not keep the name zori . The rubber sandals became known as flip-flops . Can you hear why ? “Flip-flop ” is the sound the shoes make when you walk in them . So , that's some information about the flip-flop we wear on our feet . But another way we use the word "flip-flop " in American English has nothing to do with shoes . When you flip-flop , you completely change your mind on an issue . Not only do you adjust your thinking , but you adopt the exact opposite position . For example , maybe one day you announce to your roommates that you have become a vegetarian . You plan to eat only vegetables , beans , rice and pasta . But at the end of the week , you make another announcement . You say you've changed your mind . And now , you will only eat meat . Word historians say this usage of "flip-flop " began around 1930 and comes from the world of electronics . “Flip-flop ” referred to switching circuits that alternate between two states . Today , we most commonly use the term “flip-flop ” in politics . Being accused of flip-flopping is usually not good . Let's say you are running for a political office . Early in your political career perhaps you supported a popular issue – such as tax breaks for businesses . But now supporting that issue is not popular . So , during the campaign , you tell voters that you've changed your mind . You are now against tax breaks for businesses . Your opponent could accuse you of being weak , of not knowing what you believe in , or of changing your position to get more votes . Voters come to know you as a flip-flopper . Another , more neutral expression that means about the same as "flip-flop " is “to do a 180 .” (By the way , you can spell “one-eighty ” with either numbers or letters . The pronunciation is the same .) If you turn 180 degrees around a circle , you will be facing in the opposite direction . So , you can use this term simply to mean turn around . That is the literal meaning . Figuratively , doing a 180 means you completely change your opinion , or you make a big change in your lifestyle . In our earlier example about flip-flopping from being a vegetarian to eating meat , you could also say you did a 180 . That expression sounds less critical than “flip-flop .” At work , you may not want to say that your boss flip-flopped on an important issue . Saying she did a 180 is more polite . You could also say that she reversed her earlier opinion . Better still , you can say her opinion evolved . Using the word “evolved ” gives the impression that she changed her opinion over a long period of time and after thinking about it very carefully . In other words , if you do not want to offend someone , you might want to save your flip-flops for the beach .