The World Passport is an alleged travel document issued by a non-governmental entity called the World Service Authority (WSA), which is the administrative arm of the World Government of World Citizens, to persons who are, in theory, advocates of free global travel and world government. It is one of several official-looking documents issued to people who either perceive statelessness as a desirable condition (but in practice find it to be a huge bother) or to people who have exhausted just about every other way of persuading people of the legitimacy of their person or intentions. The World Passport is generally issued to people who are either deceived or trying to deceive someone and wouldn't qualify for a Nansen Passport even if those still existed.
The idea of global government and/or documentation may be a bit older but this incarnation of global bureaucracy was invented by the WSA founder, the late Mr. Garry Davis, in 1954. This fellow also gave out "honorary" passports to assorted world leaders and celebrities. So he himself held passport number one and none other than the President, or more likely whoever in his entourage was in charge of acquired clutter, held passport number two.
The World Passport is designed to be impressive. It's a bit larger than all but the most imposingly old-fashioned national passports. It uses a startling shade of light turquoise and print similar to what you'd find in an American passport, all of it with more metallic splashes and flourishes. It was machine-readable quite early on so, until national passports caught up with it, the World Passport looked more official than many real passports, especially if you were dealing with abominations like the British and (ex-)Soviet ones, both of which were issued in chicken-scratch well into the computer age.
The fundamental problem with the World Passport is that it is issued by a non-government entity and you could get one for your dog if you tried. Issuing it in "Washington, D.C." (and for a while from a Shanghai office, you can imagine what the Chinese government thought of that) does not make it the bearer's personal pocket consular officer any more than performing fellatio on a genie will get you a 12-inch pianist. The Esperanto text should have tipped you off.
As borders have tightened across the world and air travel in particular is a bureaucratic chore for all who participate, the World Passport is increasingly likely to get you laughed at or arrested. This has always been an issue. Mr. Davis kept a record of his successful admissions and many arrests during his travels and attempted travels. The Passport's issuers claim a modicum of official recognition, which seems to have come primarily from easily impressed African bureaucrats of the younger post-colonial era.
This does not mean that no one will give you a plane ticket or apostille stamp for presenting it. All it takes is one bored clerk. In fact the organisation's web site maintains an archive of entry and visa stamps from an impressive number of countries, and requests that citizens provide images of theirs. Most of these date before the Achille Lauro incident, in which one of the arrested terrorists escaped and went a-roaming and a-missing for a while on a World Passport.
Having done my time in international travel, I saw a number of these passports (and less legitimate efforts at emulating it) so the aforementioned bored clerk was sometimes me. I really did not mind the Passport. Some people actually used it as a second ID. As long as the names matched it could give something like a dog-eared French national identity card or an Iraqi passport with scrawls in five different hands a veneer of technological legitimacy, and was a helluva lot easier to read than either.
Whether my passengers would be allowed onto the boat was not my concern. I cynically sold them the tickets and let border control deal with it. This probably makes me a worse person than you already knew I was. Mind you, I never did get a complaint from the border police, though that might have been because they were not that big on checking outbound documents and, since the holders were likely to be less than legally in the country, would just as soon let the misdocumented passengers be anyone else's problem, Schengen be praised and pass the ouzo. Unless it was the Russian mafia, which was always good for a little shakedown. Their couriers did account for an alarming portion of World Passport holders.
Just in case you think this World Passport thing sounds like something you'd like to try your luck with, here's a former transport professional's warning: This is not your grandpa's (or even my) world of international travel. Even if you manage to trick your way onto public transportation and out of a country, travelling on hokey documents will get you arrested, quizzed, and/or probed, and more likely than not will end with you and the horse you rode in on being expeditiously returned to your point of origin. Now go for it and bon voyage.
It should still be good enough to be admitted to NowhereQuest and some of the territories therein.