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# start()

Starts the animation represented by the receiver.

```
func start()
```

## Discussion

A strong reference to the animation is maintained until the end of the animation or until its [`stop()`](/documentation/AppKit/NSAnimation/stop()) method is called. If the blocking mode is [`NSAnimation.BlockingMode.blocking`](/documentation/AppKit/NSAnimation/BlockingMode/blocking), this method returns after the animation has completed or the delegate sends it [`stop()`](/documentation/AppKit/NSAnimation/stop()). If the receiver has a progress of `1.0`, it starts again at `0.0`.

## See Also

[`start(when:reachesProgress:)`](/documentation/AppKit/NSAnimation/start(when:reachesProgress:))

Starts running the animation represented by the receiver when another animation reaches a specific progress mark.


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