Why is Bizznis called a Parent Theme?
Bizznis has been built to be used with a child theme and not just as a standalone theme. We did this to speed up the development process and to take care of core WordPress theme functions, while giving developers opportunity to fully focus on unique theme features.
What is a Child Theme?
A child theme is an extension of a parent theme (like Bizznis) and is typically consisted of theme elements – a screenshot, theme files, a stylesheet, a functions file and an images folder. These elements are grouped together in what’s known as a child theme folder and can be activated like any other WordPress theme. Detailed explanation of a child theme is offered here: http://codex.wordpress.org/Child_Themes
How to create a Child Theme of Bizznis?
The easiest way would be to start with an example child theme and modify it to suit your needs. An example child theme is offered here:https://github.com/bizzthemes/bizznis-child.