A  'code of conduct'  is a set of rules and regulations about how you should behave in a particular situation.

If you were to be invited to attend a Royal Wedding, there would be a  'code of conduct'  to tell you what types of behaviour are and are not appropriate.  There is a similar 'code' for any other formal social event - wedding, funeral, etc. - though it is not normally written down.

In the US , or US jurisprudence, the word Code also refers to law. So, we have a body of law in one book called the „California Criminal Code“, the „Family Code“ and a whole host of other areas of law. The related verb is „codify“, so that you could say that a specific rule of law was now „codified“, for instance, meaning written and published as a statute, or specific law. The word has broad meanings, and a code of conduct, just as stated above, just refers to a rule of behavior that can be informal or formal. Violating a military code of conduct, for example, can have criminal consequences. But, a simple social faux paus could also be a referred to as violating a given social code of conduct, although not be serious or have any real consequences. So, it all depends on the context. 

In the US , or US jurisprudence, the word Code also refers to law. So, we have a body of law in one book called the „California Criminal Code“, the „Family Code“ and a whole host of other areas of law. The related verb is „codify“, so that you could say that a specific rule of law was now „codified“, for instance, meaning written and published as a statute, or specific law. The word has broad meanings, and a code of conduct, just as stated above, just refers to a rule of behavior that can be informal or formal. Violating a military code of conduct, for example, can have criminal consequences. But, a simple social faux paus could also be a referred to as violating a given social code of conduct, although not be serious or have any real consequences. So, it all depends on the context. 

it means the rules of behavor for any given situation/event /organisation/country etc