First of all, this is not the same question as can be found here: (Redirect URLs using Redirect component or .htaccess).
What I want to know is what HTTP Status Code (for e.g. 301, 302, 303, etc...) is by default for the Joomla's redirect component, or not being used at all?
I have read the official documentation here but with no specific explanation about the matter.
Another doc here:Creating_301_redirects suggests only a few details.
If SEO is the main concern, then the Joomla's redirect component seems to be unusable.