xml is hierarchical so css is hierarchical.
Styles applied to parent elements cascade to their
Styles applied at the most general level cascade to all
elements that ﬁt that general level.
<title>A first cascade</title>
This is body
<p>This is a default styled paragraph</p>
<p style="font-size: 24px;">This is 24px
This is more default body
So what’s this OOP
OPP has inheritance.
In object-oriented programming, inheritance is a way to
form new classes (instances of which are called
objects) using classes that have already been deﬁned.
The inheritance concept was invented in 1967 for
That’s not OOP
Type selectors are basically super classes
ID selectors are like instances of a class
Class selectors are like modules
IE 6 is broken
Almost all other
browsers follow this