When did humans start to exist?

Since species evolve and evolution is a slow but steady process it's hard to talk about "the first human". There isn't a moment in history where one animal suddenly gives birth to a new kind of species from one generation to the next. There are however small changes which can be considered drastic enough to be named as a new species.

The first hominid skeleton, named Lucy, was discovered in 1974 in Ethiopia. They dated her bones to be 3.2 million years old.

The first homo sapiens date back from little less than 200,000 years ago. They discovered a 195,000 year old fossil, also in Ethiopia which shows the first traits of skull changes which are considered to be traits of "modern humans". These traits are a rounded skull with projecting chin. Another skeleton found in the Middle Awash Area shows the same traits of these changes. They can be considered to be the "first humans" but they weren't completely like us, just partially, since evolution happens gradually.

According to The Bible and other religious factors, many people believe that the first humans were created on earth at 4,000 BC, along with every species of animal which was created with them. However, this would mean that humans and dinosaurs must have coexisted. Which has been proven to be false by scientists.