Many theories have tried to explain who made them and why, however, no single theory works.
They were made over the course of 1000 years by the Paracas, and then the Nazca people...
Here is Brian Foerster with interesting aerial shots of the Nazca Lines.
This is dummy text. It is not meant to be read. Accordingly, it is difficult to figure out when to end it. But then, this is dummy text. It is not meant to be read. Period.