Even though we instinctively think most solar systems consist of one star, actually most stars are in binary systems. It is thought that perhaps up to 85% of stars are in binary systems. With some in triple or even higher-multiple systems.
How to find Alcor and Mizar the most famous double stars in the nights sky. In fact these double stars were also the first double stars to both be discovered and photographed.
While it is, of course, easy to see Alcor and Mizar in a telescope. The minimum equipment you would need to split Alcor and Mizar into two separate stars is a good pair of binoculars.