<style= " ">
is highly uncommon, you mean style attribute:
? Well yes, css needs a way to resolve conflicting properties, so there is a point system. The property with the most points get applied.
from the top of my head:
style attribute: 1000points
id selector: 100 points
class selector: 10 points
element selector: 1 point
you should check documentation if you really want to understand this point system
<style></style> means you have an internal stylesheet, usually you have an external stylesheet (css code in separate file), its quit uncommon to use style attribute or internal stylesheet.
the external stylesheet, will make things more maintainable.