 Hi, I'm Zor. Welcome to Unisor Education. Let's continue talking about implementation of mathematical logic and computer logic, if you wish, in electronic schema using electronic devices such as diodes. Now, the previous lecture was the implementation of logical or disjunction operation. This one will be about logical and conjunction. Now, first of all, let me remind you the rules of conjunction. These are here. These are arguments. Zero means false, one means true. So the rules of conjunction are these. So only if both arguments are true, then the result will be true. Just consider it this way. For instance, A is something happens or not happens. It's true or false, whatever. And B means some other event happens or not happens. Now, if we are talking about a statement like this, both events A and B happened. When will that be true? Only if one happened and another happened, because I'm using and not or. If I'm using A or B happened, that's a completely different logic. That's a disjunction that was previous lecture. Now, this one is about and. So A and B happened. It means A happened and B happened. So A is one and B is one. All other cases where none of them is happening or one of them is happening, it means that A and B did not happen. If only one of them or none of them. Only if both of them happen. So that's the rules of conjunction. Okay. And now this is a schema which I suggest because it is a very primitive implementation of this logic. And again, let me remind you that in electronics, one is associated with a positive charge and zero is associated with zero potential. Okay. So let's imagine what happens in this case. So this is the result. This is output of my schema. And these two are input arguments A and B. So we have a battery and positive is through resistor is connected to output. So let's just think about this way. If both of them are one, it's this case, which means both of them are positively charged. Well, here is a positive charge. So there is a deficiency of electrons here. Right? Now these are positively charged, which means this termionic emission doesn't really exist in a sufficient amount because this is a deficiency of electrons. There are no electrons actually. I mean, there are some but not sufficient to create the electronic cloud to go this way. So basically, there is no change of electrons anywhere at all. The electrons are not moving. And that's why this positive charge through this resistor is here. Only if both of them are positively charged. Now what happens is one, if one of them or both of them are at zero. Well, at zero means that actually there is certain amount of termionic emission here and there is always a source of new electrons. We are maintaining at zero. So even if something actually goes this way, there is always some which comes in to maintain it at zero. Let's say it's connected to a ground, one of them. So ground is an infinite source of electrons. So if one of them is at zero, it means that it's always enough electrons if something actually went out. So electrons, in case one of them or both of them are at zero, at neutral potential, will go through termionic emission to this site. And what they will do, they will neutralize the deficiency of electrons created by positive charge and will become zero. Again, it requires certain adjustment of parameters because it all depends on this voltage or this resistor and the capacities of these two diodes as far as how much electrons are coming through from cathode to anode, obviously. But we can really do some kind of an adjustment in such a way that the electrons which are coming from here or from here will compensate deficiency here and it will become zero. So if one of them is at zero, then this becomes zero. This is all these cases. If one of them, both of both of them is at zero, which means it has this infinite source of electrons to compensate, then the result at C will be zero because the positive charge will be compensated. Basically, that's it. Again, it's a very primitive and it requires certain adjustment of parameters and it's all calculated, obviously. And this is the part which I'm not going to touch. These are for professional engineers in electronics. But I wanted to present you the idea how people actually came to implementation of logical operations through electronics. Well, basically that's it. I do suggest you to read the notes for this lecture. The lecture is part of the course, Physics 14, presented at Unisor.com. And every lecture has notes for it. And the whole website is completely free. There are no advertisements to sway you from learning. Pure knowledge, all for free. Please enjoy it. Thank you very much and good luck.