Generally, a contract is understood to be an agreement that creates an obligation upon one party. Its' basic components include (1) parties who are capable of contracting, (2) a particular subject matter, (3) legal consideration or monetary value, (4) a common ground of agreement, and (5) an obligation that is mutual between the parties.

A contract is an expression by two or more persons of common intention to effect their legal relations.  Please see specific state for details and/or differences.

ALABAMA | ALASKA | ARIZONA | ARKANSAS | CALIFORNIA | COLORADO | CONNECTICUT | DELAWARE | FLORIDA 
 GEORGIA | HAWAII | IDAHO | ILLINOIS | INDIANA | IOWA | KANSAS | KENTUCKY | LOUISIANA | MAINE | MARYLAND 
 MASSACHUSETTS | MICHIGAN | MINNESOTA | MISSISSIPPI | MISSOURI | MONTANA | NEBRASKA | NEVADA 
 NEW HAMPSHIRE | NEW JERSEY | NEW MEXICO | NEW YORK | NORTH CAROLINA | NORTH DAKOTA | OHIO 
 OKLAHOMA | OREGON | PENNSYLVANIA | RHODE ISLAND | SOUTH CAROLINA | SOUTH DAKOTA | TENNESSEE 
 TEXAS | UTAH | VERMONT | VIRGINIA | WASHINGTON | WEST VIRGINIA | WISCONSIN | WYOMING

ALABAMA
In Alabama, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

ALASKA
In Alaska, a contract is a promise between parties as a declaration by one party of his or her intention to do something or to forbear from doing something at the request or the use of another. That proposal, once accepted, becomes a promise.

ARIZONA
In Arizona, a contract is an expression by two or more persons of common intention to effect their legal relations.

ARKANSAS
In Arkansas, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

CALIFORNIA
In California, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties. It occurs when there has been a sufficient amount of consideration to do or not do a particular act that is a part of the contract.

COLORADO
In Colorado, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties. It occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

CONNECTICUT
In Connecticut, a contract is an agreement between parties whereby one of them acquires the right to an act by the other, and the other assumes an obligation to perform that act.

DELAWARE
In Delaware a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties and it occurs when a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

FLORIDA
In Florida, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

GEORGIA
In Georgia, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

HAWAII
In Hawaii, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

IDAHO
In Idaho, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act, and gives to the promisee a legal right to demand and enforce fulfillment.

ILLINOIS
In Illinois, a contract is an expression by two or more persons of common intention to effect their legal relations.

INDIANA
In Indiana, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

IOWA
In Iowa, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

KANSAS
In Kansas, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

KENTUCKY
In Kentucky, a contract is a promise for a breach of which the law gives a remedy or recognizes as an existing legal duty.

LOUISIANA
In Louisiana civil law, the definition of a contract does not differ materially from the common law definition. A “contract” has been defined as an agreement made by the consent of the contracting parties to do or refrain from doing an act specified, in reference to a definite object that may be the subject thereof, for such consideration as may be established.

MAINE
In Maine, normally it is understood that there is no difference between a contract and agreement. An agreement in some respects is a wider term. Many agreements do not produce a legal effect on the relations between the parties; however, to amount to a contract, the agreement must be of a nature to produce a binding result on the mutual relationships of the parties.

MARYLAND
In Maryland, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

MASSACHUSETTS
In Massachusetts, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act, and gives to the promisee a legal right to demand and enforce fulfillment.

MICHIGAN
In Michigan, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act, and gives to the promisee a legal right to demand and enforce fulfillment.

MINNESOTA
In Minnesota, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

MISSISSIPPI
In Mississippi, a contract is where one party binds himself or herself or becomes bound in an expressed or implied way to pay a sum of money or to do some other act or omit to do some act. It is understood that the word “contract” is broad enough to include contracts both in writing and by unwritten acts.

MISSOURI
In Missouri, a contract occurs where there is a meeting of the minds of the contracting parties who knowingly and understandingly entered into the contract.

MONTANA
In Montana, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act, and gives to the promisee a legal right to demand and enforce fulfillment.

NEBRASKA
In Nebraska, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

NEVADA
In Nevada, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act and gives to the promisee a legal right to demand and enforce fulfillment.

NEW HAMPSHIRE
In New Hampshire, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act and gives to the promisee a legal right to demand and enforce fulfillment.

NEW JERSEY
In New Jersey, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

NEW MEXICO
In New Mexico, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act and gives to the promisee a legal right to demand and enforce fulfillment.

NEW YORK
No extra details.

NORTH CAROLINA
In North Carolina, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

NORTH DAKOTA
In North Dakota, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

OHIO
In Ohio, a contract is a promise or set of promises for the breach of which the law gives the remedy or the performance of which the law in some way recognizes as a duty. This is generally construed to be the basis of a contract.

OKLAHOMA
In Oklahoma, a contract is a promise between parties as a declaration by one party of his or her intention to do something or to forbear from doing something at the request or the use of another. That proposal, once accepted, becomes a promise.

OREGON
In Oregon, a contract is an agreement between two or more parties who are competent for that purpose, upon a sufficient consideration, to do or not to do a particular thing, which lawfully may be done or omitted.

PENNSYLVANIA
In Pennsylvania, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

RHODE ISLAND
In Rhode Island, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

SOUTH CAROLINA
In South Carolina, a contract and compact are convertible and synonymous terms. A transaction is broader as a term than contract, since a contract may be construed to be a transaction. A transaction is not necessarily a contract.

SOUTH DAKOTA
In South Dakota, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act and gives to the promisee a legal right to demand and enforce fulfillment.

TENNESSEE
In Tennessee, a contract is a promise between parties as a declaration by one party of his or her intention to do something or to forbear from doing something at the request or the use of another. That proposal, once accepted, becomes a promise.

TEXAS
In Texas, a contract is a delivered engagement between competent parties to do or abstain from doing some act for a sufficient consideration. The word "competent," as used in the definition, means that both of the parties to the agreement were sane at the time it was made.

UTAH
In Utah, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act and gives to the promisee a legal right to demand and enforce fulfillment.

VERMONT
In Vermont, writing is not the crucial factor of a contract, but is written evidence of the contract. In other words, there may be a contract, although there is no writing evidencing it.

VIRGINIA
In Virginia, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act and gives to the promisee a legal right to demand and enforce fulfillment.

WASHINGTON
In Washington, a contract also is to be distinguished from an arrangement.  There is a recognized distinction between a contract itself and the obligation that the contract is the agreement of the parties; whereas, an obligation is the remedy that the law affords to its enforcement.

WEST VIRGINIA
In West Virginia, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act and gives to the promisee a legal right to demand and enforce fulfillment.

WISCONSIN
In Wisconsin, a contract is understood to be an agreement that creates an obligation that the law recognizes to include an agreement between the parties based upon a mutual understanding. It is generally an agreement between two parties; however, it may be an agreement between more than two parties, and it occurs when there exists a sufficient amount of consideration to do or not to do a particular act that is a part of the contract.

WYOMING
In Wyoming, a contract is also known to be a declaration, verbal or written, made by one person to another for a good or valuable consideration by which the promisor binds himself or herself to do or to forbear some act and gives to the promisee a legal right to demand and enforce fulfillment.