Notes

1) consideration: according to pollock "consideration is the price for which the promise of other is bought''. consideration is also defined as the element of exchange in a contract.

2) contract: according to sec2(h) of Indian contact act, an agreement enforceable by law is a contact.
it consists of two elements: an agreement
legal obligation i.e., a duty enforceable by law

3) void contract: a void contract is a contract valid in the beginning but becomes void later on due to illegality or impossibility of performance is known as a void contract.

4) coercion: the section 15 of the following act defines coercion as follows.
committing or threatening to commit any act forbidden by the indian penal code
unlawful detaining or threatening to detain a property
by the prejudice of any person whatever
with the intention of causing any person to enter into an agreement
5) bailment: sec148 defines bailment as the delivery of goods by one person to another person for some purpose, , upon a contract that they, shall when the purpose is accomplished be returned or disposed according to the direction of the person delivering them.

6) pledge: according to the sec 172 of ica bailment of goods as security for payment of debt or performance of a promise is known as pledge.