While a contract can be written or oral, the vast majority of contracts are never written or accepted with a signature. Instead, accepting a contract is usually done by exchanging money for a product or service, such as for example. B the purchase of something in a company. However, when it comes to complex contracts with several conditions, it is preferable to obtain the agreement in writing. The parties must exchange a certain value for a contract to be binding. This is called reflection. The consideration must not be appropriate or for the benefit of the other person, it must be sufficient (for example. B if someone offers to sell their home for free, there is no consideration; but if he offers to sell it for £1, then there is a valid consideration).