Fairmount City Landlord-Tenant Lawyer, Pennsylvania

The basis of a contract. Consideration is a benefit or right for which the parties to a contract must bargain; the contract is founded on an exchange of one form of consideration for another. Consideration may be a promise to perform a certain act -- for example, a promise to fix a leaky roof -- or a promise not to do something, such as build a second story on a house that will block the neighbor's view. Whatever its particulars, consideration must be something of value to the people who are making the contract.

A way two or more people can own property together. Each can leave his or her interest upon death to beneficiaries of his choosing instead of to the other owners, as is required with joint tenancy. In some states, two people are presumed to own property as tenants in common unless they've agreed otherwise in writing.

The taking of physical evidence or property by law enforcement officials. This runs the gamut from taking blood for a drug test to impounding a car used in a robbery. The police must generally obtain a search warrant, or court order, before they can seize personal property.

The causing of harm by disrupting something that belongs to someone else -- for example, interfering with a contractual relationship so that one party fails to deliver goods on time.

A legally binding contract in which a person or business promises to treat specific information as a trade secret and not disclose it to others without proper authorization. Nondisclosure agreements are often used when a business discloses a trade secret to another person or business for such purposes as development, marketing, evaluation or securing financial backing. Although nondisclosure agreements are usually in the form of written contracts, they may also be implied if the context of a business relationship suggests that the parties intended to make an agreement. For example, a business that conducts patent searches for inventors is expected to keep information about the invention secret, even if no written agreement is signed, because the nature of the business is to deal in confidential information.

A determination of the value of something, such as a house, jewelry or stock. A professional appraiser -- a qualified, disinterested expert -- makes an estimate by examining the property, and looking at the initial purchase price and comparing it with recent sales of similar property. Courts commonly order appraisals in probate, condemnation, bankruptcy or foreclosure proceedings in order to determine the fair market value of property. Banks and real estate companies use appraisals to ascertain the worth of real estate for lending purposes. And insurance companies require appraisals to determine the amount of damage done to covered property before settling insurance claims.

A promise that pledges nothing, because it is vague or because the promisor can choose whether or not to honor it. Such promises are not legally binding. For example, if you get a new job and promise to work for three years, unless you resign sooner, you haven't made a valid contract and can resign or be fired at any time.