CSS reset

CSS reset refers to setting as many values of the CSS box model to 0, in case a "stray" browser decides to add default values that differ from the other more conventional browsers.

The global selector

We use the CSS global selector, *, to apply a property-value pair to all selectors:

* { 
  border: 0;
  margin: 0;
  padding: 0;
}

Such ensures that we have no borders, margins, or paddings, for any elements, until we further specify them in our CSS!

(We could add almost any property-value pair to this asterisk selector, so that we can have more certainty of each property's values.)