What does "Third World" mean?

The term "Third World" is somewhat out of date now for at
least a couple of reasons.  However, it is generally used to refer to countries that are
very poor and underdeveolped.

The term was first used back
in the Cold War.  At that time, it referred to countries that were not part of the First
World (the rich, capitalist/democratic world) or the Second World (the poorer communist
world).  The rest of the world was all lumped together under the term "Third
World."

From there, the term gradually evolved to refer to
those countries that were poor and underdeveloped.  Social scientists are somewhat
reluctant to use the term today because it seems judgemental.  The more common term for
what used to be called the Third World is "developing world."