# `$window` (service in module `ng` )

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## Description

A reference to the browser's `window` object. While `window` is globally available in JavaScript, it causes testability problems, because it is a global variable. In angular we always refer to it through the `$window` service, so it may be overridden, removed or mocked for testing.

All expressions are evaluated with respect to current scope so they don't suffer from window globality.

## Example

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#### Demo