What about types of document which must be in writing and/or signed to be valid?
Certain types of contract will only legally binding and effective if in writing and signed, e.g. a contract for the sale or other disposition of an interest in land.
However, they do not need to be on paper or signed in “wet ink”. In these cases, a document in electronic form is still in “writing” and an electronic signature is still a “signature”. Therefore an exchange of emails can amount to a binding contract for various types of transaction. As an example, it is even possible that, in relation to a real property sale, a chain of emails between solicitors can amount to a legally binding contract.
This means that it is easy to enter into a binding contract inadvertently. You might in fact not have intended to do so because, for example, you have not yet reached agreement on all terms or have not set out all of the terms in the emails. For tips on how to avoid such an unintended consequence, please see the Guidance Note: Electronic Signature of Deeds and Contracts.
Some types of document also need not only to be in writing and “signed” but also to comply with other requirements.