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Before we get into any c++
code that uses pointers,

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let's see what a pointer is.

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A pointer is a variable.

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Okay, we know all about variables.

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Variables have an address in
memory where they're bound to.

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They also have a type, such as int,
double, string, vector and so forth.

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And they have a value,
which they store.

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A pointer is a variable and
it stores the address of

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another variable or function.

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So if I initialize an integer
variable named x to 10 then

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x is of type integer and it's
bound to some memory location,

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and it contains the value 10.

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That means that I can declare
a pointer variable that

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stores the address of x.

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So a pointer is a variable.

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That means that the pointer has a
memory location where it's bound to.

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It has a type, it has a value,
and the value is an address.

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We'll see how to declare a
pointer in c++ in the next video.

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Remember that a pointer points
to a variable or to a function.

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To use the pointer, you must know
the type of what it points to.

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Before we learn about how to
use pointers, let's see why we

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use pointers in the first place.

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If a pointer points to a
variable or a function, can't

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i just use the variable or
the function directly, sure.

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And if you can, you should.

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There is no sense in creating
a pointer to something

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that you can use directly.

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But you can't always do that.

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For example, if you have some complex
data that's defined outside a function

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and you want to access that data from
within the function, you can't because

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the variable name is out of scope.

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So you can pass the data to the
function by value and make a copy

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of it or you can use a reference
or a pointer parameter to access

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that data from within the function.

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Also pointers are often used to
operate on arrays very efficiently.

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In fact, we'll see in this
section just how interrelated

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pointers and arrays are.

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We can use pointers to allocate
memory from the heap or the free

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story dynamically at runtime.

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That memory doesn't have a
variable name associated with it.

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So the only way to use
it is through a pointer.

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Finally, if you're working with
embedded systems, device drivers

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or other types of system software,
sometimes you need to gain access

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to a specific memory address
or a range of memory addresses.

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Pointers is the best way to do that.

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Okay, now that we know a little
bit more about what a pointer is

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and why we would use one, let's
see how we can declare a pointer

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variable in the next video.