What is what does xxx mean?

The term "xxx" can have multiple meanings depending on the context in which it is used. Here are a few interpretations:

1. Roman Numerals: In Roman numerals, "XXX" represents the number 30.

2. Movie Rating: In the context of films and entertainment, "XXX" is often used to indicate content that is intended for adults only, typically of an explicit sexual nature.

3. Kisses: In informal written communication, particularly in the UK and some other countries, "xxx" can be used at the end of a message to represent kisses, conveying affection or friendship.

4. Brand or Title: "XXX" can also refer to a brand, product, or title. For example, there is a film series named "xXx" starring Vin Diesel, which centers around extreme sports athletes turned government operatives.

5. Placeholder Text: In coding or documentation, "xxx" might be used as a placeholder text, similar to how "foo" or "bar" might be used, indicating that actual content or a specific name is to be inserted there.

If you provide more context about how "xxx" is being used, I can give a more specific explanation.