child marriage is illegal in India and hence it is an illegal and void contract

Void is there never was an enforceable contract. For example, a contract for murder is void, but it is for an illegal act. No one can sue in court and have it enforced by a judge.



Voidable is a valid contract, but one of the parties has the right to cancel it. For example, a contract made by a minor can be cancelled by the minor.

A void contract is considered to be a legal contract that is invalid, even from the start of signing the contract. On the other hand, a voidable contract is also a legal contract which is declared invalid by one of the two parties, for certain legal reasons.

While a void contract becomes invalid at the time of its creation, a voidable contract only becomes invalid if it is cancelled by one of the two parties who are engaged in the contract.

In the case of a void contract, no performance is possible, whereas it is possible in a voidable contract. While a void contract is not valid at face value, a voidable contract is valid, but can be declared invalid at any time.

A contract can become void if it involves any illegal activity, if the contract is made in such a way that it cannot be executed, or if the contract is not properly structured. An example of a void contract is a contract between a drug dealer and a buyer. This type of contract is void because it involves an illegal activity.

There are many reasons attributed to a voidable contract. It is a situation where one party of the contract may repudiate it. A contract involving minors is an example of voidable contract. Although minors can enter into contracts, these agreements cannot be enforced, as minors are at liberty to change their stand.

While a void contract is nonexistent and cannot be upheld by any law, a voidable contract is an existing contract, and is binding to at least one party involved in the contract.

Summary:

1. While a void contract becomes invalid at the time of its creation, a voidable contract only becomes invalid if it is cancelled by one of the two parties who are engaged in the contract.

2. A contract can become void if the contract involves any illegal activity, if the contract is made in such a way that it cannot be executed, or if the contract is not properly structured.

3. A voidable contract is where one party in the contract may repudiate it.

4. A void contract is nonexistent and cannot be upheld by any law. On the other hand, voidable contracts are existing contracts, and are bound to at least one party involved in the contract.

Void Means "NOT ALLOWED". Any act which is not as per provisions of Either any existing Act or Constitution is considered void. Even if any Contract is entered which is VOID, then it will not have any effect and the parties will not be able to sue each other in Court of Law.

Voidable means a contract which is enforceable at the option of the Aggreived (Read Victim party) but not at the option of the other party (Read Perpetrator party). Though it is rarely possible that the victim party will be benefited by the contract, but changed circumstances may lead the Victim party ultimately beneficial.

see

void means....

"jisko enforce karwane ke liye tum doosre par case or suit file nahi kar sakte "

and

illegal means

"jo galat hai kanoon ki nazar mein "

difference between void and voidable 

1. While a void contract becomes invalid at the time of its creation, a voidable contract only becomes invalid if it is cancelled by one of the two parties who are engaged in the contract.

2. A contract can become void if the contract involves any illegal activity, if the contract is made in such a way that it cannot be executed, or if the contract is not properly structured.

3. A voidable contract is where one party in the contract may repudiate it.

4. A void contract is nonexistent and cannot be upheld by any law. On the other hand, voidable contracts are existing contracts, and are bound to at least one party involved in the contract.

Difference between Void And Illegal 

well xplained by lakshmi

A contract is based on an agreement. An agreement becomes a contract when all the essentials elements of a contract are present. In such a case, the contract is a valid contract. If one or more of these elements is / are missing, the contract is either voidable, void, illegal or unenforceable

i)         Voidable contract: An agreement which is enforceable by law at the option of one or more of the parties thereto, but not at the  option of the other or others, is a voidable contract [Section 2(i)]. This happens when the essential element of free consent is a contract is missing. When the consent of a party to a contract is not free, i.e. it is caused by coercion, undue influence, misrepresentation or fraud, the contract is voidable at his option. [Section 19 and 19-A]. A voidable contract continues to be valid till it is avoided by the party entitled to do so.

Example: A promises to sell his car to B for Rs. 2,000. His consent is obtained by use of force. The contract is voidable at the option of A. He may avoid the contract or elect to be bound by it.

ii)       Void agreement and void contract:

Void agreement: An agreement not enforceable by law is said to be void [Section 2 (g)]. A void agreement does not create any legal rights or obligations. It is void ab initio.i.e.,from the very beginning as, for example an agreement with a minor or an agreement without consideration.

Void contract: A contract which ceases to be enforceable by law becomes void when it ceases to be enforceable [Section 2(j)]. A contract, when originally entered into, may be valid and binding on the parties, e.g. a contract to import of goods from a foreign country. It may subsequently become void, e.g. when a war breaks out between the importing country and the exporting country.

It is illogical to talk of a void contract originally entered into, for what is supposed to be a contract is no contract at all. We may talk of such a contract as a void agreement.

Please read the full text of attachment contianing classification of contracts to have the better understanding.