(or "You mean there's no one flying the plane?")
The Internet was born in the 60s and 70s as a special project of the Advanced Research Projects Administration (ARPA). Rumors persist that the original goal was to develop a way to transmit information that could not be interrupted by nuclear attack. True or not, one of the major goals was to get the ability for scientists and researchers to share information with each other, quickly and efficiently. Thus was ARPANet born. An initially small network connecting a few research sites together. Compared to the Internet we know today, it was puny and slow - but back then, it was a miracle.
Bit by bit, universities were connected to the ARPANet. Although it was still being used to help researchers, and only prestigious universities who did a lot of work with computers had them (U.C. Berkeley and M.I.T were among the earliest members of the ARPANet), it was at least growing. Slowly, the Internet grew faster and universities started allowing students to use the ARPANet. Growing at a rapid pace, it quickly became used for eMail and student correspondence. More features and standard capabilities were added with time; FTP, Gopher and then the World Wide Web... Eventually ARPA pulled out of the project and committed the Internet to the future.
Nobody exclusively controls the Internet now. Different providers, universities or people control small portions of the Internet, but any one of them could be replaced if necessary. Likewise, there is no-one to force their opinions or will on the 'Net - Nobody can say "I don't like that web page, have it removed". You can temporarily stop someone from saying something, but it's not permanent. The Internet exists as world's largest co-operative effort, ever. Pretty grandiose, huh? And it's getting bigger all the time.
Now, various organizations control different parts of the Internet and set standards for what can be used on them. Educational sites typically only host non-commercial information used or maintained by students and faculty of the institution. Government sites host public resources. Military sites often don't host anything the general public is supposed to see, but they use the Internet too, as well as their own, private network. Commercial sites are unregulated and can have pretty much anything on them. You can tell what kind of site you're on by looking at the name:http://www.somewhere.com
is a Commercial site. It ends in ".com". Educational institutions usually end in ".edu", Military in ".mil", government in ".gov", non-profit institutions can use the ".org" ending. Then there's tricky endings: Two-letter endings are usually countries; ".us" is the USA (most US sites don't use the .US ending though, since the Internet started here and for a long time it was taken for granted. Other countries are '.au" (Australia), ".nz" (New Zealand), ".ca" (Canada), ".uk" (United kingdom) and dozens more. Furthermore, each country also uses the com, edu, mil, org and gov endings; they are, however, usually shortened to two letters; .co, .ed, .mi, .or and .go . There are many exceptions, and each country can set themselves up however they wish. The UK uses ".ac" (for Academic) instead of ".ed". Australia typically uses all three letters. So... ".edu.au" is an educational institution in Australia, and ".ac.uk" is an educational institution in the UK. Confusing? Perhaps. You generally don't need to know where you're going as long as they give you the information you want though. If you have a choice between two or more sites to use, pick the one that looks closest. If you live in Australia, an ".au" site is preferable to a ".uk" one, for instance. Information doesn't have to be passed so many times and can get to you faster the closer it is.