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[MUSIC]

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One of the benefits of JavaScript is
that it allows us to build websites and

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applications that people
can interact with.

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This interaction is often in the form
of user input, like entering words or

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other characters into a web form.

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As a JavaScript developer,
you will often work with this user input.

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For example, you might have to
remove whitespace or search for

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values within user input.

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When it comes to storing user input,

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JavaScript commonly relies
on the string data type.

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The string type Describes
variables made up of letters and

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other sequences of characters
wrapped in quotation marks.

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Strings can include not only letters,
but also numbers and symbols.

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strings in JavaScript
are said to be immutable.

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This means they can't be altered or
updated.

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JavaScript treats the string similar
to an object, providing properties and

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built in methods that allow us to
access and manipulate string values.

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These methods can't change the value
of a string once it's defined,

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but instead,
return a completely new string object.

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Let's open up the console and
give this a try.

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We'll take the familiar
to uppercase method and

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apply on a variable named state,
that stores the string California.

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We'll first define the variable

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We'll need to make sure that
all the letters are lowercase.

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Now we'll apply the two uppercase
method to the state variable.

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We see CALIFORNIA in all capital letters.

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But when we check the value of state
again, it's still in all lowercase.

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String methods take
the value of a string and

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output values based on
the selected method.

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With string methods, we use the format
string dot methodName, parentheses.

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Many of these string methods take
an index value as a parameter.

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Like with arrays, bracket notation allows
us to access string characters using

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index values that start at zero.

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For instance,

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we can access the third character of
a string using bracket notation by

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passing in the number two to access the
item at index two using bracket notation.

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Access the character at
zero of our state variable.

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The console will log out C.

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Nice.

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Coming up,
we'll explore two groups of methods.

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Those for searching a string and
methods for modifying a string value.