What is difference between using Url::to or Url::toRoute in yii2?

The only difference is that Url::to() method requires a route to be specified as an array only. If a string is given, it will be treated as a URL.

// /index.php?r=site/index

echo  Url::toRoute('site/index');

// /index.php?r=site/index

echo Url::to(['site/index']);

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