One of the first things you need to consider when buying a tripod is that it will safely support the size and weight of your camera and any lenses you plan to attach to it.
Small and lightweight, a mini-tripod easily fits into a camera bag or purse. It can be placed on a table top or other level surface when needed. There are also heavy duty mini-tripods that have the features and flexibility of their full-sized counterparts.
Some mini-tripods can be held against your chest to provide camera stability and prevent camera shake when there is no place to set down the tripod.
A compact tripod has the height and most of the features of full-sized tripods but is lightweight. A compact tripods folds so it can be placed in a suitcase. Some can not hold a camera more than a few pounds.
Often the choice of professional and serious photographers where traveling light is not a concern, full-sized tripods can hold heavy cameras with long telephoto lenses. They have heavy duty construction and offer a variety of special features.