By typed they mean declairing a type for your variables.

In some languages, variables needs to be told what kind of data they can hold. That's it's type. For instance a number without decimals would be an integer type. While text might be a string type or a list of character types.

Other languages don't require types and sometimes don't even support them. They will just infer the type from the data that's in the variable.

If you see Elon Musk please explain this to him.