# Directory Structure
The Mini Program comes with an app directory that describes the overall program and multiple page directories that describe the respective pages.
The main part of a Mini Program is composed of three files that must be placed in the project’s root directory:
| File | Required | Description |
|---|---|---|
| app.js | Yes | Mini Program logic |
| app.json | Yes | Common configurations for Mini Program |
| app.wxss | No | Common style sheet for Mini Program |
A Mini Program page is composed of four files:
| File Type | Required | Description |
|---|---|---|
| js | Yes | Page logic |
| wxml | Yes | Page structure |
| json | No | Page configuration |
| wxss | No | Page style sheet |
Note: To reduce the number of configuration items developers have to deal with, the four files that describe a page must have identical paths and file names.
# Files allowed for upload
In the project directory, the following files are compiled and thus cannot be accessed directly after they are uploaded: *.js, app.json, *.wxml, and *.wxss (wxml and wxss are only for pages configured in app.json). In addition to these file types, only files with suffixes in the following whitelist can be uploaded:
- wxs
- png
- jpg
- jpeg
- gif
- svg
- json
- cer
- mp3
- aac
- m4a
- mp4
- wav
- ogg
- silk