Are Magento Object propertyNames that are prefixed by “_” different from ones that aren't?

Question

what does this tell me ? Is there a place in the devdoc's I wasn't able to find or is this a convention I don't know about? thanx for your help...

Answer 1

Magento 2 follows the PSR-2 coding standard, which states:

4.2

Property names SHOULD NOT be prefixed with a single underscore to indicate protected or private visibility.

4.3

Method names SHOULD NOT be prefixed with a single underscore to indicate protected or private visibility.