# Tilde Friends Developer's Guide
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A Tilde Friends application runs on the server.  To make an interesting
application that interacts with the client, it's necessary to understand
how the parts work together.

## Hello, world!

A simple starting point.  Presents `Hello, world!` in the browser when
visited.

**app.js**:
```
app.setDocument('<h1>Hello, world!</h1>');
```