</div>
        <div class="bx--row">
            <div class="bx--col-sm-4 bx--col-md-5 bx--col-lg-8 toolMain">
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### Why is this important?

When the language attribute is used to identify the default human language of the page, the attribute value must conform to [BCP 47](https://www.rfc-editor.org/rfc/bcp/bcp47.txt). 
This ensures that user agents and text-to-speech (TTS) synthesizers can correctly present the page's default content using the 