Chainsaws are big and powerful pieces of equipment. They can have many uses in the outdoors, for cutting down trees, hedges and branches. More often than not they are used by professionals and usually equipment like this will only be sold to qualified tree surgeons who can prove what they do for a living.
The best chainsaws are very light so that they can easily be used at height. They will usually be petrol operated and some are more environmentally friendly than others depending on their emissions. Some chainsaws will have an anti-vibration system and an easy start system in place, making them easier to use. Make sure to always use them as instructed and to wear safety equipment where required, such as protective clothing and headphones to block out noise. Chainsaws are by no means cheap so if you are thinking about buying one, choose a good brand that comes with a guarantee.