Every star is unique, no two of them are exactly the same. All stars have evolved from extremely hot gases at the beginning of their lives, called nebulae, and then into cold rocks, called white dwarfs, that sit on the ends of their radiators. Stars can only be found by the outer space, infrared, or gamma-ray satellites. No one knows how stars are born, or if there is a way to tell if a star has already been born. All we know is that all of them are created within our galaxy and are undergoing a constant process of evolution like all other stars.
Stars in the main sequence stars are very much similar to our sun. They have hydrogen atoms and produce energy through nuclear fusion. All other stars look different because they contain an excess of one of the components of hydrogen (atoms containing one electron) or another element (atoms having multiple electrons). The only real difference between stars is the number of elements they contain, and the speed with which they spin.
Stars that are in the main sequence are very different, because they have a very slow rotation rate and a high mass. The stars in this group tend to form clouds of gas that are not rotating, and they are much cooler than the other stars. They are also farther away from the solar system, because they are further away and therefore have less gravity. They are very unique in that they are the only ones with clouds of gas that are not rotating, and therefore they do not experience a mean pull from the solar system or from one of its satellites.