This is not an easy question to answer. Debates rage over which fossils can be called truly hominoid (humanlike), or hominid (human).
The development of human characteristics took place over millions of years. The earliest primate (an order of mammals that includes humans, apes, and monkeys), no bigger than a rat, appeared 60 million years ago.
About 10 million years ago, the Ramapithecus showed remarkable hominoid attributes. But there is no further evidence until 6 million years later.
The first generally accepted hominoid is called Australopithecus, and some believe they are actually the most primitive of the human lineage.
Homo habilis, dating back at least 2 million years in modern-day Africa, is undisputedly human. Less than a half-million years later, Homo erectus lived in Africa as well as in Asia and Europe.
A fossil skull fragment discovered in England is the oldest known example of modern-day humans: a 300,000-year-old Homo sapien.