In the previous sections,
we learned about data fetching
and we learned about data mutations.
And what you already saw there,
at least in certain situations,
was that data may sometimes not update,
or the pages that display the data may sometimes not update
as expected because NextJS does some caching for you.
And that's exactly
what we'll take a closer look at in this course section
because in this section we'll analyze how exactly
NextJS caches data and pages,
and what that means for you.
You will learn how you can get NextJS
to revalidate cached data
and throw away cached data
so that updated data is displayed when needed.
And we'll also take a look at
how you can control which data is being cached
depending on which data source you are using.