To write programs using `ftd` language you will have to use `fastn`, a command
line program, like `ls` we mentioned in previous section. `fastn` is a
"compiler" or "interpreter" of `ftd`, it converts your `ftd` programs to `html`,
`css`, `js` that browsers understand. `fastn` is also a "package manager", when
you are writing programs, you often depend on code written by others, shared by
them to make life easy by everyone. Code you depend on others is called
dependencies or libraries. We call them `fastn package`. And `fastn` manages
these packages. This will all make sense more sense as we progress in the book,
what you need to know is that `fastn` acts as your package manager as well. And
finally `fastn` is a "web server", when you write a web application or a website,
you are trying to create something that works in web browsers like Chrome,
Firefox, Safari, etc, and these browsers talk to "web servers".
So `fastn` is all that for you, and more. So let's install it now. If you are
using `OSX` or `Linux`, installing it can be as easy as running the following
in the terminal:
sudo bash -c "$(curl -fsSL https://raw.githubusercontent.com/fastn-stack/fastn/main/install.sh)"
Copy the command above by clicking on the copy icon, and paste it in the
terminal. It will ask you to enter your super user password so it can do the
installtion.
NOTE: A note on caution, when using terminal, it is generally not a good idea to
trust random sites and run the commands they ask you to run. We have done this
as a convenience, and it is recommended you follow other methods described in
our [installation manual](/install/).
This is how a successful installation looks like:
NOTE: [People have reported that the above step does not work on some
networks](https://github.com/fastn-stack/fastn/issues/619), please consider
switching your network to rectify this problem.
Installing on Windows
We have not yet made installing `fastn` on Windows very easy, instead we have a
[guide for Windows users](/windows/-/book/). Please follow it and come back
here.
Verifying Your Installation
Once you have installed `fastn`, you should be able to use the `fastn` command
from your terminal. Open a terminal and type `fastn` command, you should see
something like this as the output.
If you see something like this, congratulations, you are ready to rock! If not,
please head over to our [Questions & Answers
forum](https://github.com/fastn-stack/fastn/discussions/categories/q-a) or on
our [Discord](https://discord.gg/a7eBUeutWD) server.
Next Step
Now that you have `fastn` installed, let's install a [programming
editor](/book/editor/).