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Welcome back, everyone.

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We're going to have two lectures on control flow and the first lecture.

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We're talking about comparison and logical operators, which we can use to return back a Boolean.

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Let's check it out.

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All right.

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Here I am inside of the Visual Studio code editor.

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The first thing I want to talk about is comparison operator.

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Just a quick tour of all of them.

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So comparison operators allow you to compare two separate pieces of data or elements.

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For example, we've actually already seen one.

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Something like one is greater than two.

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So this greater than symbol, that's the comparison.

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Operator And we can actually print out the results.

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So something like this one is greater than two or check if one is greater than two, really.

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We'll go ahead and run that and we get back false.

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So you should expect comparison operators to return back a brilliant either true or false.

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And there is greater than.

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Less than.

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And then there's greater than or equal to.

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So go ahead and check out this one.

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And then there's less than or equal to so less than or equal to.

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There is not equal, so not equal as exclamation mark equal.

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So this tax is one not equal to two.

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We would expect that statement to be true.

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It's true that one is not equal to two.

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And then for checking equality, it's just two equal sides.

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Be careful because beginners often forget that it's to equal science and they try to do something like

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this.

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Remember, one equal sign is an assignment, so here you'd be kind of breaking Python by saying, OK,

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one is actually equal to two now, so you want to be super careful of something like that.

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I remember it's two equal science for comparison.

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So let's go ahead and say something like two is equal to two.

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Check this out.

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And now we get back.

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True, I remember this doesn't just have to be numbers, it can also be with strings.

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For instance, I can say something like my record for an employee is, let's say, lowercase was a.

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And then maybe I have some sort of match that I want to check out.

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And it also happens to be Jose.

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And then later on in my logic, I want to check if is the record equal to the match that I looked up

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from somewhere else.

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So that's the kind of thing you're going to be seeing a lot checking if, Hey, does this actually match

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some sort of lookup?

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All right.

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So we can obviously do a comparison operators with variables.

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Now, if you want to combine multiple comparison operations, that's where logical operators come into

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play.

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So for example, let's say I want to check both.

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That one is greater than two and at two is less than three.

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How would I actually do that?

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Well, the main logical operators type that interest, so we make sure so we're now talking about logical

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operators.

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These are going to be key words like and and then or.

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So how does this work?

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I can say print is one greater than two and is to equal to two.

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So for the and operator, you're going to need both of these statements to be true.

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So we know one is not greater than two.

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And then even if this is true, this one is false.

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So since both are not true, we would expect this to be false.

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We run this code and we get back false.

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Let's go ahead and change this.

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So we can say is three get greater than two and is to greater equal to two.

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We'll go ahead and save that.

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We expect this to be true because now both statements are true.

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If I need either statement to be true, that's worthy or operator comes into play.

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So this will return back a Boolean if either of these is true.

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So, for example, I'm going to say again, one is greater than two or two equal to two.

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So because one of these happens to be true, we should get back true here.

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OK?

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And that's basically it for the logical operators and comparison operators we work with throughout the

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course.

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There's a couple more things here, but we're going to introduce them later on.

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The main idea being is you have this ability to check for equality of two equal sides or check for inequality

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with exclamation mark, equal sign, and then you can combine multiple checks like that with and statements

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or statements.

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OK.

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So what's going to do one last quick example here?

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So we can get kind of a use case here.

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So we're going to say user input is equal to.

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And let's go ahead and say my password and we'll say stored.

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Password.

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Is my password, so you can imagine if someone is using our website and we were able to get back their

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user input as my password and then we have their stored password as my password.

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We can check for equality.

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So then I could just print, Hey, is user input equal to the stored a password I have?

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Now, obviously, you wouldn't store a password in plaintext, but you get the idea here.

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This is the sort of check we can do with a comparison operation.

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OK.

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So what comparison operators and logical operators we can begin to learn about, if else, statements?

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I'll see you there.