For all those who don't know: Wild camping is legal in Scotland. If you want, you

A fell wall is a dry stone wall that denotes property boundaries. The lowest, near the roads, you could think of as the “front.” The highest is the “back” of the property and anything above it is fair game for public use like camping.

More importantly a cell wall is a rigid layer of polysaccharides lying outside the plasma membrane of the cells of plants, fungi, and bacteria. In the algae and higher plants it consists mainly of cellulose.

Thank you. You have no idea how difficult it is to get an explanation of that

So you can camp almost anywhere in Scotland as long as it is not private land that is normally defined by a fence or wall. We do not have mosquitoes, but do have tiny biting insects call Midgies. If you camp near water you can get hundreds of bites that just leave itchy sores. However any hunting grade bug repellant will keep them away

I understand about Scotland but don't understand about others countries =)

In Sweden it's allowed under the "rights of public access" (allemansrätten) with the exception of nature reserves. Basically you're allowed to camp for a 24 hours just about anywhere as long as you don't disturb other people or wildlife and as long as you're careful with fire and pick up your trash. You're allowed to pick most berries and mushrooms but hunting and fishing requires a licence.
Google "allemansrätten in English" for more information.