The impact of different types of contract

Type of the contract	Impact
Simple or oral contract is a legally binding contract, but it carries a risk.	It is difficult to enforce in the court because there is no evidence of the terms.
Contract in deed or written contract provides evidence of the terms and allows both parties to study terms – that makes a contract enforceable. Some contracts are only legal if they are in writing (property selling e.g. buildings).	The impact of the deed is that it makes it legal.
Void contract is not a contract. It never was a contract – it is void ab initio. e.g. Selling something you do not own is a void contract. A contract for an illegal act is also void.	The impact of a void contract is that goods sold can be recovered, even if they have been sold on to a third party.
Voidable contract is a contract which can be made void in particular situations, for example one party is a minor. The contract is legally valid until it is made void.	The impact is that goods can be recovered unless they have already been sold to a third party, which would have been legal.
Unenforceable contract is legally binding, but cannot be enforceable by a court, for example there is no enough evidence.	The impact is that both sides are obligated to perform their part of the contract, but the court will not make you.
Unilateral contract is an offer made to the world at large, where acceptance is the performance of the duty specified. e.g. reward poster	The impact is that contract is formed when performance is carried out or begun to be carried out.
Electronic contracts e.g. emails	The impact is that have the same effect as written contracts.
Collateral contract is contract where one contract is used as consideration for another.	The impact is when one contract can be used as consideration for another.

Analysis of terms in contracts with reference to their meaning and effect

Express and implied terms

	Express terms	Implied terms
Meaning	An express term is a term expressly agreed by the parties to contract to be a term of that contract.	Implied tern is a term deemed to form part of a contract even though not expressly mentioned.
Effect	Express terms cannot over side terms implied by the statute. However, express terms can over side terms implied by custom.	Terms implied by the statute ‘Sale of Goods Act 1979’. They protect you and cannot be taken away. Terms implied by custom – the way it is always done.