Here's what we know:
* Native speakers: Around 13 million people in Greece and Cyprus speak Greek as their native language.
* Second language speakers: There are significant communities of Greek speakers in countries like the United States, Australia, Canada, and the United Kingdom, primarily due to historical migration.
* Total estimate: Some estimates place the total number of Greek speakers worldwide at around 14-15 million. However, this is a very rough estimate and may not be entirely accurate.
It's important to note that these figures do not include people who may have learned some Greek but do not speak it fluently or regularly.