In addition to strings integers and floats
variables can also contain boolean values a billion value is simply true are false.
These are useful because we can use them when controlling programme flow.
Ah what a program should do next.
We'll see this in detail later on.
To assign a billion value to a variable used the word true are the word false.
Note that we don't have quotes around the values.
You can write it in upper case a lower case but it's best practice to put it in lower case like this.
A variable can also contain a special value called No.
No is used to represent a variable that has no value.
A variable is null if no value has been assigned to it yet.
Ah if it's assigned the value null like this.
As with billions.
Note that there are no quotes around this value and it can be upper and lower case but the convention
is to write it in lower case.
As with numbers we need to be careful with variables like these.
The first one contains a boolean value.
Well the second one contains a string with the word true.
These are not the same.
Likewise the first variable here is null while the second one contains the four characters N U L L.
Again these are not the same.
Let's look at an example of some of these variables.
Let's add a boolean and a nold variable.
And again will use the.
Far don't function to print out these values.
This time however instead of calling ghafar Dump twice once for each variable.
I'm only going to call it once passing in two variables at the same time.
The violent function lets you pass in as many variables as you like.
Will learn more about passing values to functions later on.
So back in the code we'll pass our two variables to the vihar Dump function like that.
Then in the browser when we open our p-h P file we see the values printed out.
First a boolean are bool value of true and then a no value.