Should I use Camel Case or does it really matter?

Does it really matter if I use Camel Case or Underscore?

For readability I try to stick to the core style.

Ok thanks, but do you think it is OK to use underscore, it will not break anything or cause any problems etc?

It wouldn’t cause any errors but might cause some unexpected results.

If you named an action

public function action_name()

it wouldn’t work as the framework is expecting

public function actionName()

Ok thanks.