# Source files and projects

[Syntax and values](README.md)

The ending of a filename is its **extension**. It labels a file type; renaming the ending does not convert the contents. A project **manifest** is its information card, including which source file starts the program. [File extensions](../concepts/file-extensions.md) and [manifests](../concepts/manifests.md) explain both terms.

Pliro has two source containers:

| Form | Purpose |
|---|---|
| `.pliro` | One standalone [UTF-8](../concepts/utf-8.md) source file. |
| `.bipli` | A portable project containing a manifest, one or more `.pliro` sources, and optional assets. |

A standalone file cannot resolve project-local modules or packaged assets. A
`.bipli` project can contain both.

Project commands have deliberate scope. `check` validates every project source.
`run`, `build`, and `emit-model` begin at the manifest entry source and
initialize its reachable modules dependency-first. [CLI](../concepts/command-line.md) `fmt` and CLI
`translate` target the entry source while preserving or checking the
surrounding project as described in
[Section 19](../../../pliro-syntax.en.md#19-formatting-and-command-line-tools).

## Related entries

[Syntax and values](README.md) · [Built-ins](../builtins/README.md) · [Programming guides](../guides/README.md)