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Now that we know how to assign variables, let's talk a little bit more about

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the data types

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that we are using.

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So quite simply, with respect to Python, there are many different data types

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that you can

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utilize in this particular video though.

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What I want to focus in on is the string data type as well as the integer.

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So let's first begin with this one here.

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This sounds pretty strange.

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What an earth is it.

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Well, the good news is that we've all ready to deal with it.

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See for example, this right here, this happens to be a string.

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Now really in your mind, just conceptualize a string as a sequence of
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Now really in your mind, just conceptualize a string as a sequence of

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characters.

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It's basically used as the word text data.

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Now this text data can also include things like numbers.

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Say for example, if I wanted to add in the value of John 2001 at example.com as

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an email

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in the current context, this is all just one sequence of characters.

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So realistically, when we want our variable value to be a word or to be a

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sentence, that

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type of thing, the type of value we're going to be using is a string value

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versus

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if we want to utilize numerical values, then we would use something known as an
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if we want to utilize numerical values, then we would use something known as an

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integer.

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Now why is this actually important?

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Let me just show you why.

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Okay.

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That's a pretty variable here.

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Let's just say name is equal to John.

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Okay.

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Now watch this.

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If I just print out name right here, save this.

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If I try to run the example as it's down right here, look at this right there.

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It says we have a name error and the name John is not defined.

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So what exactly is going on here?

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Well, because this is going to be an order that sequence of characters, IAA

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string value,
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string value,

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the way we actually assign this is we make sure that the value is within

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quotation marks.

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Watch what happens when I put the quotation marks.

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See this?

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This actually goes away.

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They're a little warning sign.

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And if I just rerun the script, suddenly we actually print out the value.

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So what this actually means is that the use of the quotation marks is actually

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very,

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very important.

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Let me just highlight to you why.

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So that's a pretty variable called first number.

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Now if I give it the number, let's say 10 and I use the quotation marks here,
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Now if I give it the number, let's say 10 and I use the quotation marks here,

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we're

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actually not using in numerical value, we are really using a string.

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So then if I say the second number is equal to and again, I add in with

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quotation marks

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the number five and I then say the total number is equal to and I take the

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first number

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and I add it to the second number and then I try to print the value of the

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total number.

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What do you think the value is going to be?

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Now mathematically, if you look at this, you would say, well, 10 plus five is

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equal to 15

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and we give this particular value to the variable total number.
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and we give this particular value to the variable total number.

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So we should be printing out the value 15.

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This is not what we're going to see though.

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Check this out.

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If I just run this, look at what we actually get here.

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Because we have defined each data type as a string value, they are being

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treated as ordered

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sequences of characters, not as numerical values.

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So realistically, all that is happening here is we've taken the first number,

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which is

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one zero and then we've added on the second number, which is a five and we've

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given the total
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given the total

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value of one or five.

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So obviously this is a little bit of a problem, very much so though, when you

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want to be dealing

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with these numerical values that actually have some type of mathematical

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context.

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Now really quite simple to define an integer.

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All we do is we actually use a number of value in the numerical value, I say,

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and we do

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not actually use the quotations.

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Now just to be clear here, if I only did this once, watch what happens, I'm

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trying to add

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an integer to a string.

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If I run this again, we're going to get a problem.
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If I run this again, we're going to get a problem.

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It's going to give us a type error.

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It's going to say we cannot actually add an integer and a string together.

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So check this out.

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If I now specify the value here, I'm now using integers.

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If I just are up and rerun this, now we're getting that mathematical operation.

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Now let me just show you one very good function that you can use with respect

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to your data

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types.

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We actually have a type function that will tell you the type that is used

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within a particular
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within a particular

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variable.

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So I just happen to print out the type here and I run the script, but actually

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seeing

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we are returning an integer, whereas if I put both of these values within quot

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ations right

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here, again, we're going to be concatenating strings together.

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If I run it now, we can see we're returning a string value.

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So this is a very good way to eyeball the information that you're using.

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Now these are just two of the data types that we can be using.

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And one last thing to note here, remember I said how Python was dynamic.

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We can just assign variable values without defining the data type.
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We can just assign variable values without defining the data type.

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Watch this.

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Say for example, I changed this to five.

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We know right here, if I just try to print this out as it is, you're doing

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these parentheses,

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let's just save this.

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We know as it stands, this is going to give us an error as such.

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Now we know what I can do is take my variable here and just dynamically reass

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ign it so I can

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just reassign it right there.

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So the first time it was defined, it was a string value stored as this

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particular variable

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first number, but then we just modify it to completely different type.
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first number, but then we just modify it to completely different type.

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So we're not just updating the value of the same type, but actually changing

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the type entirely.

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Watch what happens now because we are able to dynamically update this.

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And I run the script.

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Suddenly, everything is working quite just fine.

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So the key take home points right here to note are the data types that we

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assign to particular

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variables actually can have a profound effect on the execution of our program.

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And as we can see here, Python, being a dynamic language does not require us to
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And as we can see here, Python, being a dynamic language does not require us to

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manually specify

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which data type we want to be using when creating our variables.

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They can just be modified as we need.

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And Python will just accept those values dynamically.

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So now we know about strings and integers, the next data type that I want to

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talk to about

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are lists and dictionaries.