# Getting started with PyScript
This page will guide you through getting started with PyScript.
## Development setup
PyScript does not require any development environment other
than a web browser. We recommend using Chrome.
## Installation
First, go to https://pyscript.net and download the PyScript assets.
Unzip the archive to a directory where you wish to write PyScript-enabled
HTML files. You should then have three files in your directory.
```
├── ./
│ ├── pyscript.css
│ ├── pyscript.js
│ └── pyscript.js.map
```
## Your first PyScript HTML file
Here's a "Hello, world!" example using PyScript using the assets you
downloaded from https://pyscript.net.
Using your favorite editor create a new file called `hello.html` in
the same directory as your PyScript JavaScript and CSS files with the
following content and open the file in your web browser. You can typically
open an HTML by double clicking it in your file explorer.
```html
print('Hello, World!')
```
Notice the use of the `` tag in the HTML body. This
is where you'll write your Python code. In the following sections we'll
introduce the 8 tags provided by PyScript.
## The py-script tag
The `` tag let's you execute multi-line Python scripts and
print back onto the page. For
example we can compute π.
```html
print("Let's compute π:")
def wallis(n):
pi = 2
for i in range(1,n):
pi *= 4 * i ** 2 / (4 * i ** 2 - 1)
return pi
pi = wallis(100000)
s = f"π is approximately {pi:.3f}"
print(s)
```
### Writing into labeled elements
In the example above we had a single `` tag and it printed
one or more lines onto the page in order. Within the `` you
have access to the `pyscript` module, which provides a `.write()` method
to send strings into labeled elements on the page.
For example we'll add some style elements and provide place holders for
the `` tag write to.
```html
Today is
import datetime as dt
pyscript.write('today', dt.date.today().strftime('%A %B %d, %Y'))
def wallis(n):
pi = 2
for i in range(1,n):
pi *= 4 * i ** 2 / (4 * i ** 2 - 1)
return pi
pi = wallis(100000)
pyscript.write('pi', f'π is approximately {pi:.3f}')
```
## Packages and modules
In addition to the [Python Standard Library](https://docs.python.org/3/library/) and
the `pyscript` module, many 3rd-party OSS packages will work out-of-the-box with PyScript.
In order to use them you will need to delcare the dependencies using the `` in the
HTML head.
For example, NumPy and Matplotlib are available. Notice here we're using ``
as a shortcut, which takes the expression on the last line of the script and runs `pyscript.write('plot', fig)`.
```html
- numpy
- matplotlib
Let's plot random numbers
import matplotlib.pyplot as plt
import numpy as np
x = np.random.randn(1000)
y = np.random.randn(1000)
fig, ax = plt.subplots()
ax.scatter(x, y)
fig
```