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So far, the conditional statements we've
created provide just two possible paths.

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Let's call them door number one,
door number two.

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If a condition is true, like the user
entered a name in an input field,

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the program passes
through door number one.

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But if the condition is false, then the
program passes through door number two.

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But what if you want many
different outcomes, not just two?

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In our daily lives,
we're used to many possible outcomes.

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For example,
say it's your day off from work and

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you're trying to figure out what to do for
the day.

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Your first step might be to find
out what the weather's like.

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Based on this, you could plan your day.

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For example, if it's hot and

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sunny, you might go swimming, if it's
snowing, you might go sliding or skiing.

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If it's raining,
you might stay in and read a book.

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You can't do all three, only one, and each
choice is based on a series of conditions.

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If it's hot and sunny,
if it's snowing, if it's raining.

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JavaScript also includes a way for

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a program to provide multiple outcomes
using what's called an else if clause.

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All right, now let's open the else-if.js
file inside the js folder and

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as usual, update the script tag and
index.html so that it points to else-if.js

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So else if works like this,
you start with an if statement.

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Then add an else if clause,
which provides another condition to test.

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So now you have two conditions.

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If the first one is true,

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then the code in the first block
between the first pair of braces runs.

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Let's call this door number one.

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However, if the first condition is false,
then we test a second condition.

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If the answer to that condition is true,

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then the code in the second
code block runs.

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Let's call this door number two.

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The second condition is not tested
if the first condition is true.

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This is important.

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You'll only get to the second
condition if the first is false.

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Now, if neither of the conditions is true,
you might want to provide a fallback,

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door number three, so
that the program does something.

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You can do this by adding
an else clause to the end.

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Notice how there is no condition for
this last part.

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However, the code block at
the end only ever runs if both of

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the conditions above are false.

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And there's no limit to the number
of else if clauses you can add.

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But remember that you must
start with an if statement and

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the else clause, if there is one,
must go at the end.

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So now there is three test conditions and
four possible outcomes.

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And keep in mind that as soon as one
test condition is true, the code for

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that condition runs, and
all the conditions following,

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including the very last
else clause are skipped.

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Now, let's see how you might use this
conditional statement in a program.

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Earlier, I gave some examples of
activities you can do based on weather

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conditions.

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For instance, if it's snowing,
you could go sledding.

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Your first step might be to find
out what the weather is like,

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based on that you could plan your day.

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And the first condition, I'll check if
weather strictly equals the string, sun.

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If it's sun, log the message it's sunny,
so I'm going swimming.

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In the else if clause, I can check
if weather strictly equals rain.

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And if it's rain, log it's raining,
so I will read a book.

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I'll have the next else if clause
check if weather strictly equals snow.

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And if so, then log the message,
it's snowing, so I'm going sledding.

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Now, the else block at the end only
ever runs if all three of these

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conditions are false.

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In that case, log the message,
I don't know what I'm doing today.

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Before testing this code, I need to
declare the weather variable, and

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assign it either sun, rain, or snow.

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I'll try rain first.

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I'll save my code.

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And over in the console,
since weather = rain, I see the message,

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it's raining, so I will read a book.

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I'll try sun.

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Then snow.

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And it works.

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Now if I change the value of
weather to an empty string or

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anything other than rain,
sun, or snow, for example.

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The console prints,
I don't know what I'm doing today.

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So as you've learned, an else if clause
provides a way to make a program more

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flexible and able to respond on
to multiple conditional outcomes.