Does having the same last name as another, mean that you are related to them som

Question:

Does having the same last name as another, mean that you are related to them somehow?

If they aren't, how exactly do you end up having a bunch of people with the last name Smith?...or Nguyen? Does Nguyen mean anything, or is it equivalent to names designating an occupation or locale (Smith/macher=maker, Berg=town)

Best Answer - Chosen by Asker: One (of many) "sources" of a surname, as you mention, comes from occupation. Thus, you could certainly have 2 or more persons with the same job, and their descendents eventually wound up with the name. But there never was a relationship to start with. It also is very possible that a particular name "started" in more than one location or country, with completely unrelated persons. So, contrary to common thought, names do not always have one country of origin or nationality. Names go back to the 1300's in some areas, or even earlier. Remember.. this might only be the only RECORD of a name, not the only place it was used.
Another common misdirection, is to assume that there was ONE immigrant of a name, and everyone descends from him. There could be an immigrant in the 1600's from one locality overseas, and another unrelated line that migrated in the 1800's.
This is one reason why it is so important to build a firm foundation to research, by tracing back one generation at a time. By doing this, you are certain of your "connection" as you go, and don't waste time working unrelated records.
If you have a rare surname, your odds of being related go way up.