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OK let's build upon where we just left off with the boolean expressions.

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So now let's talk about relational operators and boolean operators.

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So what do we mean when we say operator let's go ahead and just add a new section here and we'll just

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say relational and boolean operators if you want.

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You can go ahead and just put a new line here.

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So remember we specify a new line in a function and let's say greater than let's define a variable called

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greater than and let's just make that equal to seven is greater than five.

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OK.

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So we're using a operator here with the greater than symbol right.

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And we're also using a boolean expression because when we say seven is greater than five.

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Well that's going to come back with true.

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And we could say less than we could say five is less than seven.

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And that's also going to return true What about the greater than or equal to we can say seven is greater

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than or equal to seven.

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And that's going to return true as well.

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And then if you can think of less than or equal to it's going to be very similar we say seven less than

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or equal to seven.

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And that's also going to be true.

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So if we were to print all of these out which we don't have to they're all going to return back true

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so there's other things that we can add in here.

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So what if we bring in multiple operators.

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For example we could say test and you can call this whatever you want.

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So what if we say seven is greater than five and five is less than seven.

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So we see here that this is true and this is true.

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That would make this entire statement true so you could say true here if we were to say let's just call

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this test and to we were to say seven is greater than five which is true and five is greater than seven.

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Well that's not true.

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So this whole statement is going to be false because we're going to say and and is very important here.

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Right.

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What if we were to say something like or though if we were to say let's test out or we could say seven

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is greater than five or five is less than seven.

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Well this is going to return true and if we were to do the same thing as we did above where we say test

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or two and we say seven is greater than five or five is greater than seven forgotten by parentheses

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here and this is also going to return true.

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Why.

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Because only one statement has to be true here for these both to be true in the instance of and both

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statements here have to be true in order for it to be true.

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If one of them becomes false the whole thing becomes false in the sense of or the case of.

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Or if both are true it's true if one or the other is true then it's true.

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Both have to be false for it to actually return false.

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OK so you can print these out as well to test this out.

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The other thing that we can say is we could say something like test not.

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We can say something like not true.

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And guess what.

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Not true is going to be false.

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And we said not false then that will be true.

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So these are the ones that can start to kind of get confusing.

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So again my recommendation is to make good notes on this and then go out and study it.

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And there are two false charts.

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Let's just see if we can google one quickly.

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There are true false charts online.

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We can say True False chart by phone and go to images and we can see truth tables is what they're called.

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So if A is true and B is true that a and b our true if A is false or true and B is false then they're

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both false false true is false and false false is false.

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So in order to have a truth table for and everything has to be true.

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So if we search truth tables that might give us a better chart here and then you get something sort

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of like this or you have and where you see a true true is true you have or where true false is still

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true and then X or we don't have to worry about right now so take good notes on these.

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Make sure you understand them.

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We're going to continue to build upon them over time.

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Really all you have to think about though is you have to think about boolean operators and these expressions.

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And the most important things to take away from this are not just the true and false but the greater

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than symbols the less than symbols.

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All these different types of operators that we can utilize here and that we can also utilize things

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such as and or and not as well.

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So we're just adding more tools to our toolkit and more things to think about where python is important

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when it comes to pen testing is not necessarily being able to develop.

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And I've said this before I must say it again being able to read and understand what is going on is

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super important.

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Being a developer not as important.

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So as long as you see these things and you see a true or you see a statement like this when you're reading

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code and you say hey I know that's a boolean operator I know it's true or false.

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And I kind of understand the truth tables.

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Right.

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So that's really what we're after here.

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So as long as you start getting this understanding and comprehension that's really what we're after.

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So from here we're going to move on and we're going to go into conditional statements and that is where

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we get into something called if then else and we'll have a little bit of fun with those.

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So I will catch you over in the next video.