# Electron

[Electron](https://www.electronjs.org) is a cross-platform (Linux, Windows,
macOS) way for creating desktop apps using TypeScript.

Electron embeds Chromium and Node.js in the generated app's binary. The
generated app thus consists of two separate processes - the _main_ process, and
a _renderer_ process.

-   The _main_ process is runs the embedded node. This process can deal with the
    host OS - it is conceptually like a `node` repl running on your machine. In our
    case, the TypeScript code (in the `src/` directory) gets transpiled by `tsc`
    into JavaScript in the `build/app/` directory, which gets bundled in the
    generated app's binary and is loaded by the node (main) process when the app
    starts.

-   The _renderer_ process is a regular web app that gets loaded into the embedded
    Chromium. When the main process starts, it creates a new "window" that shows
    this embedded Chromium. In our case, we build and bundle a static export of
    the [Photos web app](../web/README.md) in the generated app. This gets loaded
    by the embedded Chromium at runtime, acting as the app's UI.