"Human kind" and "mankind" are both used to refer to all humans. However, "mankind" has a historical bias towards referring only to men, making it potentially problematic.

Here's a breakdown:

* "Mankind" is a traditional term that has been used to refer to all humans, but it carries a connotation of "man" as the dominant figure. This can be seen as excluding women and other genders.

* "Human kind" is a more inclusive term that explicitly refers to the entire human species, regardless of gender. It avoids the historical baggage associated with "mankind."

In conclusion:

* "Human kind" is the more inclusive and appropriate term to use when referring to all humans.

* "Mankind" can be considered outdated and potentially offensive in modern usage.

It's important to be aware of the connotations of language and choose words that are respectful and inclusive.