Small systems called, protogalaxies, produced the first stars in our universe. These protogalaxies are predicted to have formed between 100 and 250 million years after the birth of our universe. They measure 30 to 100 light years across and were 100,000 to one million times more massive than our sun. These systems were made up of 90% dark matter and the rest of ordinary elements, mainly hydrogen and helium. Dark matter and ordinary matter mixed to form the first stars.
The formation of stars in this system is a lot simpler than the star development in our current universe.
The current leading theories suggest that the distribution of hydrogen throughout the early universe was such that only very massive stars could form and as such none could be surviving today.
Recent evidence has suggested an alternative scenario in which moderately energized or warm dark matter could allow the formation of stars of lower mass than previously thought.
Although this theory is in its early stages if this is possible than it is more likely than previously believed that some low mass stars could have survived to this today.
As with the stars of today, the early stars which formed 13 billion years ago, some 100-200 million years after the big bang, have varying life spans according to mass.
The high mass stars which would have formed in the early universe would have had brief (even less than only a million years) but brilliant life spans as the stars which formed in the early universe are believed to have been exceedingly more massive than even the most massive stars of today.
It is believed that the majority of early stars formed in cold dark matter scenarios and would therefore have been exceedingly massive and capable of fusing heavy elements near the end of their lives.
The super-massive black holes situated at the center of various galaxies are believed to have been formed by the collapse of these incredibly massive early stars.
The early universe was devoid of heavy elements; all heavy elements were formed through nuclear fusion in these massive early stars and then blown throughout the universe in cataclysmic supernovae.
Since the first generation of stars the speed of formation has moved from a relatively slow speed to producing new stars at a prodigious rate.
The following link is a video showing the formation of early stars.
http://www.youtube.com/watch?v=cWOidJW7ZpU