Long ago, the ruler of a far distant land had a great idea. One day, while visiting his scholars in his dungeon, he noticed that the most productive ones had bribed the guards to pass little pieces of paper back and forth between them. So he caused to be created a little fenced-off hole just inside the palace walls and gave his scholars leave to write down their thoughts on their abstruse topics then pop the papers into the hole. The idea was so novel that, as the whimsy struck them, the scholars would sometimes saunter over to the hole and rummage through the pieces of paper there. If they came across anything that struck their fancy they would scribble their thoughts on another piece of paper and toss it into the hole.
Well, years went by and the king saw that his idea was good. Every now and then a rummaging scholar would find just the thing to complete a new theory and the king would soon have gunpowder and flush toilets and so on. The king's bounty was munificent and as the kilobytes of data in the hole grew, so too did the tribe of scholars. Alas, both grew so much that the little hole had to be redug over and over again. Soon it became a pit, then a ditch, then a pond. Eminent scholars started losing their lives mining for information in the datapond. Others would start babbling madly as their brains caved in under the thought of all those lovely megabytes of data in the pond with so little ability to get at them.
Finally, the scholars demanded thread and seamstresses so that they could stitch together related pieces of paper. Pulling on one scrap of paper would then bring with it all other scraps with related scribblings so that there would be less need to descend into the pond itself. This, they claimed, would make the invention of toilet paper and cannons happen much more quickly. Grudgingly, the king agreed and made it so.
More years went by and as the scholars toiled they enlarged the datapond until it contained gigabytes of data and spread over a sizable chunk of the palace grounds. Naturally, this attracted the attention of the whole kingdom, who found it great fun. They petitioned the king to let them add pieces of paper to the datapond too. Who knows, maybe some famous scholar would one day stumble over their idle babblings, find them important, and make them famous.
Thus the years rolled by and the inventions flowed thick and fast. As they mounted, the population of the little kingdom increased enormously and soon the datapond became a datalake. By this time the people were spending so much time and energy creating and linking little bits of paper that they had little time to rummage for themselves. The lake was becoming a write-only memory. Fortunately for everyone, a famous hunter saved the day by training a troop of wild monkeys to descend into the datalake on command and find various pieces of paper. The kingdom celebrated for a whole week after that.
Alas, as the lake grew into a sea, and then into an ocean, even the little monkeys were hard pressed to find things. You see, they weren't very smart. If they were told exactly what was out there then they might do a better job of finding things. As it was though, since no one knew exactly what was in the ocean, most people often phrased their commands to the monkeys very badly. Often the monkeys then either found nothing relevant or they found such a mass of linked paper that no one could read it all. The people began to see that they needed a map of the terabytes of data swarming in the huge dataocean they now lived next to.
Of course, one day the map of the information in the dataocean grew so large that the people started crying out for maps of the map. But that is a story for another day.