Elton Eminent Domain Lawyer, Pennsylvania

A right to use property, acquired by a long tradition of open and obvious use. For example, if hikers have been using a trail through your backyard for ten years and you've never complained, they probably have an easement by prescription through your yard to the trail.

A deed that transfers whatever ownership interest the transferor has in a particular property. The deed does not guarantee anything about what is being transferred, however. For example, a divorcing husband may quitclaim his interest in certain real estate to his ex-wife, officially giving up any legal interest in the property. Compare grant deed.

A doctrine that prevents a defendant from re-litigating an issue after it has been lost. For example, if your neighbor sues you for putting up a fence on his land and the court rules that your fence extends beyond your property line, you can't later file your own lawsuit seeking a declaration that the property line is incorrectly drawn.

A rental agreement or lease between a tenant and a new tenant (called a sublessee) who will either share the rental or take over from the first tenant. The sublessee pays rent directly to the tenant. The tenant is still completely responsible to the landlord for the rent and for any damage, including that caused by the sublessee. Most landlords prohibit subleases unless they have given prior written consent. Compare assignment.

A guarantee about the quality of goods or services made by a seller, such as 'This item is guaranteed against defects in construction for one year.' Most express warranties come directly from the manufacturer or are included in the sales contract. If you want to hold the seller to an oral guarantee, it's best to get it in writing or have witnesses to the guarantee so that it doesn't come down to your word against the seller's if a problem arises.

A meeting of the minds. An agreement is made when two people reach an understanding about a particular issue, including their obligations, duties and rights. While agreement is sometimes used to mean contract -- a legally binding oral or written agreement -- it is actually a broader term, including understandings that might not rise to the level of a legally binding contract.

Principles of international law so fundamental that no nation may ignore them or attempt to contract out of them through treaties. For example, genocide and participating in a slave trade are thought to be jus cogens.