Spotting scopes are primarily used by bird watchers or as general observation and usually fixed to a tripod. Prices can vary dramatically, you generally pay more for a larger objective lens which lets more light in and the type of optics used in the construction of the scope. You can normally change the eyepiece for a different magnification or zoom eyepiece with variable magnification. Spotting scopes come in a straight or angled design, there are pros and cons to both types and it depends on where and what you intend to observe as to which design would suit best.