basically, ethics:morals::superego:ego, in that morals are internalized but ethics are imposed by an outside authority.

ethics are an outgrowth of human society/interaction on a large scale and almost always imply a system of agreed upon rules and behavior. for example, legal ethics define how a lawyere is supposed to act and conduct himself while in the course of practicing law. medical ethics do the same for medical professionals. these have nothing to do an individuals personal feelings about right or wrong, but merely what is agreed upon but society in a specific context.

morals, otoh, are an internalized set of rules that may or may not be part of a larger overarching system. these tend to be much less black and white than ethics. to make things confusing, morals can also mean a specific case of how an ethical system is applied, in which case a society can have morals.

practical examples:

doctors are ethically obliged to heal every patient he has to the best of his ability. a specific doctor might consider it immoral to let a murderer live when you have the chance to kill him/her. if a killer (to keep things less grey, assume that the killer is a killer with 100% certainty and no extraneous circumstances), comes before the aforementioned doctor with a wound, the doctor has a range of choices: kill the murderer/patient, heal him/her as best as possible, make a halfhearted attempt to heal the patient/murderer. anything less than healing the patient as best as possible would be unethical because the doctor is supposed to ignore personal biases when treating patients. according to the doctor's ethics, anything other than killing the patient/murderer is immoral.

almost all societies hold that killing another human is unethical. almost all societies have a standing army that is ethically obliged to kill enemies of the society. depending on how you want to look at this paradox, the exceptions to the broad ethical rule of not killing humans has many moral exceptions/loopholes on a societal scale, or you could say that soldiers live by a separate ethical code from the rest of society, under which killing is not forbidden.

there are at least two conflicting ethical codes when it comes to piracy/copyright infringement:

1) depriving someone of their possessions is wrong (aka stealing, ie if i am using it you can't use it), barring a few caveats 2) one should share one's knowledge freely (ie sharing is caring), barring a few caveats

deciding which ethical code takes precedence is a moral issues.

"'ethics' is either the organised philosophical study of the concepts and principles involved in systems of morality [i.e. a 2nd-order enquiry of morality], or it is the set of principles, attitudes, aims and standards adopted by individuals or organisations by which they live and act [i.e. a superset of morality]".