Reading the text of the Wikipedia article, I think it does make a distinction between the two styles. string interpolation is the process of evaluating a str

Reading the text of the Wikipedia article, I think it does make a distinction between the two styles. string interpolation is the process of evaluating a string literal containing one or more placeholders, yielding a result in which the placeholders are replaced with their corresponding values. I read this as saying that the evaluation of the string literal yields a string where the substitution has already been made. That's not the case with the format style of "string interpolation." You provide a template string and call a function with some arguments, and that replaces the placeholders. The string literal does not handle the substitutions itself. I believe the Wikipedia article agrees that this is the deciding factor. A few sentences later, the article includes this statement: Some languages do not offer string interpolation, instead offering a standard function where one parameter is the printf format string, and other(s) provide the values for each placeholder. This sounds pretty similar to what was in Python prior to this release (especially if you know how methods work in Python). Also notice how the statement begins by saying that not all languages offer string interpolation. I think that's the final nail in the coffin of the argument. You could use virtually any language to write a function that handles substitutions in template strings. If that qualified as string interpolation then every language would have it. Since some languages do not, I think we can safely say that we're talking about a syntax feature.