 When you are producing something any work that you do people work hard they get exhausted things happen you have checklist but you will still find that some mistakes will slip through how can we create a process so that these mistakes don't happen again it's okay to make mistakes once but don't keep making the same mistakes again and again. So that's where pokayoko was introduced poka means inadvertent mistake and yoke means prevent how can we prevent mistakes from happening. Let's look at before we get into examples I'll just sort of quickly classify the two types of poka yokes that exist and once you see them you'll be able to start connecting the dots together there are two types of poka yoke devices the first one is what is called control poka yoke and the second one is what is called warning poka yoke. Now in a control poka yoke the process is designed in such a manner that you would not be able to make a mistake you would actually go through the process step by step yourself without even realizing what's going on what's happening and you'd get the right thing done there is no chance of an error occurring in that process and the other process is a warning poka yoke which means that the moment the error occurs is going to flash some sort of a message to you or some sort of a warning to you to tell you oops looks like you made a mistake right so these are these two categories ideally in an ideal world we would like things to never go wrong right so we would try and aim for control poka yokes as much as possible but you would automatically as we proceed through the talk realize instances where it makes more sense to have warning poka yokes rather than having control poka yokes so let's look at some of the examples in the manufacturing industry let's say I have the engine which is going to be very hot I have some sort of a component that's really hot and I want to make sure that I make use of bolts which are heat resistant but I have other bolts also which I am using for my manufacturing process right how do I ensure that the worker doesn't go and screw on the wrong bolt you screw on the wrong bolt everything will work fine right now but after some point in time when it gets hot that bolt is going to break crack melt something is going to happen so you're going to go and have to check right later down the line okay did the guys use the right bolt so what you would do a simple solution most of us will come up with let's color coded right so let's color code the bolt and I'll immediately know but what if a person is so there are people by the way you cannot distinguish colors you won't even come to know but there are people I suppose it's difficult to believe so a more elegant solution to this is make the size of the bolt slightly different from all the other bolts that's quite simple now he's not going to be able to put the wrong bolt in it's which becomes a control pokai of mechanism so you make special the heat resistant bolts which are most likely going to be the more expensive components of your parts slightly different in size from all the other bolts it will work both ways those bolts will not fit in a low expensive place and it will also work in the right place so it's it sort of has a nice healthy