The signature has been the prime method a person uses as a proof of identity, and as a material expression of intent and execution of documents. A signature on a document indicates the provenance of the document and the intention of the signatory with regard to that document. With the advent of the electronic era, a form of signature is adopted for electronic documents. This chapter examines the regulation, use and security of electronic signatures and the types of electronic signatures, such as digital signatures and SSL technology, being used in electronic commerce.

Traditional signatures

Understanding an electronic signature involves understanding the purpose and use of the traditional signature. The status of traditional signatures has been taken for granted or assumed. The law has developed for centuries with notions of deeds and documents being signed, sealed and delivered, witnessed, notarised and so forth. In some situations a signatory is bound on signing, and in others the signatory is not bound until there is an affirming act. The underlying intention of the signatory may be to be bound only by the subsequent act of delivery. There may be many signatures on a contract: one person may sign intending to be bound by the terms of the contract, while another is merely a witness, with no legal interest in the terms. Their intention is paramount.