How to understand a specific bit of WordPress syntax

That’s a Shortcode.

It may be possible to find the function that renders that shortcode and copy/paste it into your own plugin, making it theme-independent, however, how easy that will be to do depends on how the shortcode works- if it depends on additional php functions, JavaScript, and CSS embedded within the theme.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)