When using Intent.putExtra() and Intent.getStringExtra(), are we working with the Bundle?

Simple and silly question, but I couldn't confirm it yet.

From what I understood and tested, Intent.getStringExtra() is the same as Intent.getExtras().getString() (assuming we have data to fetch).

From the documentation, what Intent.getStringExtra() does:

Retrieve extended data from the intent.

Is Intent.getStringExtra() extracting this extended data from its Bundle?

Please provide a reference to your answer.