A contract is like a promise between people. Each person or organisation who agrees to do something in a contract is called a party. An agreement, or a contract, says what you and the other person or organisation have agreed to do. It is a written list of the promises you have made.

No. according to Indian Contract Act a minor cannot enter into a contract.

Law means a 'set of rules' which governs our behaviour and relating in a civilized society. So, there is no need of law in a uncivilized society.

(i) A voidable contract is one which is enforceable by law at the option of one or more of the parties thereto, but not, at the option of other or others [Section 2 (i)]. .
(ii) A contract is voidable when one of the parties to the contract has not exercised his free consent.
(iii) Examples of voidable contracts are those which are induced by coercion undue influence, fraud, or misrepresentation.
(iv) In all these cases the person whose consent was not freely given may avoid the contract.
(v) Thus, where 'A' threatens to kill 'B' if he does not transfer his house in 'A's favour for a very low price, the agreement is voidable for being the result of coercion.

(i) According to Section 2(a) of the Indian Contract Act 1872, defines proposal as "When one person signifies to another his willingness to do or to abstain from doing anything, with a view to obtaining the assent of that other person either to such act or abstinence, he is said to make a proposal or offer."
(ii) The person who makes the proposal is generally called the 'offeror' and the person to whom it is made is called the 'offeree'.
(iii) Example: 'A' offers to sell his car to 'B' A is making an offer to do something i.e. to sell his car.

On the Basis of the Formation:
1. Express Contract:
i) A contract made by word spoken or written.
ii) According to Section. 9, in so for as the proposal or acceptance of any promise is made in words, the promise is said to be express.
iii) For example P says to Q "will you buy my bicycle for Rs.1,000?" Q says to P "Yes".
2. Implied Contract:
i) The implied contract is one, which is not expressly written but understood by the conduct of parties.
ii) Where the proposal or acceptance of any promise is made otherwise than in words, the promise is said to be implied.
iii) For example A gets into a public bus. There is an implied contract that he will pay the bus fare.
3. Quasi Contract:
i) It is a contract created by law. Actually, there is no contract.
ii) It is based on the principle that "a person shall not be allowed to enrich himself unjustly at the expense of the other".
iii) In other words it is an obligation of one party to another imposed by law independent of an agreement between the parties
4. Tacit Contract:
i) A contract is said to be tacit when it has to be inferred from the conduct of the parties.
ii) For example obtaining cash through automatic teller machine, sale by fall of hammer of an auction sale.

Sl.No	Basis	Contract	Agreement
1	Definition	A contract is an agreement enforceable by law	An Agreement is every promise or every set of promises forming consideration
2	Enforceability	Every contract is enforceable	Every promise is not enforceable
3	Inter-relation-ship	A contract includes an agreement	An Agreement does not include a contract
4	Validity	Only legal agreements are called contracts.	An agreement may be both legal and illegal
5	Legal obligation	Every contract contains a legal obligation	It is not necessary for every agreement to have legal obligation.