Science is not exact...but there is a lot of shit to support these theories.
1. Did we evolve from monkeys?
Humans did not evolve from monkeys. Humans are more closely related to modern apes than to monkeys, but we didn't evolve from apes, either. Humans share a common ancestor with modern African apes, like gorillas and chimpanzees.
Scientists believe this common ancestor existed
5 to 8 million years ago. Shortly thereafter, the species diverged into two separate lineages. One of these lineages ultimately evolved into gorillas and chimps, and the other evolved into early human ancestors called hominids.
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Human Evolution
2. How did humans evolve?
Since the earliest hominid species diverged from the ancestor we share with modern African apes, 5 to 8 million years ago, there have been at least a dozen different species of these humanlike creatures. Many of these hominid species are close relatives, but not human ancestors. Most went extinct without giving rise to other species. Some of the extinct hominids known today, however, are almost certainly direct ancestors of Homo sapiens. While the total number of species that existed and the relationships among them is still unknown, the picture becomes clearer as new fossils are found. Humans evolved through the same biological processes that govern the evolution of all life on Earth. See "What is evolution?", "How does natural selection work?", and "How do organisms evolve?"
http://www.pbs.org/wgbh/evolution/library/faq/cat02.html