In civil law jurisdictions usufruct is the right to use a good which belongs to another, and to enjoy its fruits. It should be distinguished from rent or loan (commodate). The following example should illustrate this.
Suppose that Alice owns an apple tree. When Bob has a right of usufruct on her apple tree, he could use it at will and could he sell the apples to third parties, while he is allowed to keep the revenues (the fruits) for himself. However, Alice is not allowed to revoke Bob’s right of usufruct, though he has the obligation to keep her property in good condition.
In general the right of usufruct exist for life, i.e. in above example Bob is entitled to use the apple tree until his death. Also in case he would sell his usufruct to Carol, this right ends with his death, even if Carol should survive him. But Bob could also decide to renounce his rights earlier, probably after an offer of monetary compensation by Alice.
Closely related to usufruct, is the right of use. The latter differs from the former, in that a right of use cannot be alienated by the holder.
A right of usufruct can be established by contract, but is usually the result of inheritances. For instance if Alice and Bob are married with children Carol and Dave, and Bob dies at a certain moment, it is possible that his children inherit all his property both under the condition that Alice is entitled to use it until her own demise.
You might wonder why one should establish a right of usufruct? Suppose one is a retired home-owners with only a small pension and most of one’s wealth is in one’s house. Unless you sell your home, it does not really matter whether your home is worth a million or just a few quarters. But if you sell your home, you cannot live there anymore.
So our retired home-owners has a dilemma. However, if (s)he would sell his/her house under the condition that (s)he remain the right of usufruct on the house. Though the home-owner should accept a lower price than in case (s)he would have sold in a “normal” manner.
One could wonder why someone would want to buy a home, which one could only use after (a long period of) time. Though this might not interesting for people who are looking to a house to live in, it might be interested for investors. Not only would such house less expensive, they might be able to profit of an increase of house prices after time. Or the government could, as way of social security, create a fund which would buy with this construction homes of the elderly.
Devolution [this link is under construction]