The Nameless

Characters without a name are a specific method of Playing With Nominal Importance, which can impact the story in several different ways.

Generally speaking, the more of a character's name that we hear, then the more important they are to the story. Just "we don't know their name", on it's own, isn't significant. The Bit Character is unlikely to have a name, because their impact on the story is low. When a character "doesn't have a name", but are so important to the story that they are given a name anyway, it tells us more about the story. It might be as simple as the janitor who is called "Janitor", or they may have an external reference for the name.

If the work has no name, please see No Title.

Compare the following tropes, because they often overlap:

If you have arrived here from a wick describing a character, please correct that wick to the appropriate Sub-Trope.
http://tvtropes.org/pmwiki/pmwiki.php/Main/TheNameless