| Act of Parliament | | Also known as legislation or a statute, an Act of Parliament is a written law passed by both Houses of Parliament (the Commons and the Lords), eg the Data Protection Act 1998. |
| Administrative Law | | The branch of law that governs public bodies (including NHS bodies) in the exercise of their functions. |
| Airwave | | Radio wave used in radio and television broadcasting. |
| Anti-virus | | Anti-virus software is used to prevent, detect, and remove malware, including computer viruses, worms, and Trojan horses. |
| Asset Register | | A list of property owned by the organisation. |
| Audit | | An official inspection, or evaluation, eg that the organisation’s processes are being complied with. |
| Authentication | | Ensuring that the identity of a subject or resource is the one claimed. |
| Availability | | Ensuring that information is accessible and usable upon demand by authorised users. |