Sam Bull

<p>Sets the site locale dynamically according to visitor preference.<br />
This preference comes from the user’s browser.</p>
<p>To install all available translations click the ‘Install All’ button in Settings->General.<br />
To install individual locales, select the site language and save changes for each locale you want to install.</p>
<p>Technical details:<br />
    Will parse the Accept-Language HTTP header and find the best matching language for the user from the translations available on the site.</p>


Preferred Locale

Select site locale/language according to user preference (set in their browser).

Katsushi Kawamori

<h4>Automatically switch the locale according to the locale of the browser.</h4>
<ul>
<li>Can specify multiple locale of browser.</li>
<li>Can import and export browser locale and WordPress locale configuration file with CSV.</li>
</ul>


Locale Auto Switch

Automatically switch the locale according to the locale of the browser.

Preferred Locale vs Locale Auto Switch