Consider the following example:
In the above example,
we repeatedly use the value 120
in three different places.
Let's say we need to replace 120
with the value 123,
we would have to go through
the whole code
and
replace all occurrences of
120 with 123.
This will become a tedious task
for a large code.
Here, we can use a variable
to store the value 120
that is repeatedly used,
as shown in the example below.
In the above example:
-
const length = 120 stores the value 120
in a variable named length.
We say that the value 120
is assigned to the variable length.
-
Now that we have the variable length,
let's replace 120 with this variable.
-
const is a keyword
used to create a variable.
We will talk about what const
stands for in an upcoming chapter.
If you are coming from other programming languages, then it will be confusing to see const to declare a variable.
A few chapters later, we will explain how const works in detail.