Binoculars are often referred to by two numbers separated by an "x". For example, 8x32. The first number is the power of magnification of the binocular. With an 8x32 binocular, the object being viewed appears to be eight times closer than you would see it with the unaided eye. The amount of magnification depends upon the application the binoculars are designed for. Hand-held binoculars have lower magnifications so they will be less susceptible to shaking. A larger magnification leads to a smaller field of view.
If you are looking for a good all around binocular a magnification of 8 to 10 is probably ideal, and most of the binocular manufacturers offer a wide range of options in the 8x42, 10x42, 8x50, 10x50 ranges. Long range and high magnification binoculars, such as the ones used for star gazing – have magnifications in the range of 40-100 and require a heavy duty tripod due to their size and weight.