Full Disk Encryption (FDE): A security measure used to protect all data on a hard drive. By encrypting every bit of data, including files, folders, and the operating system itself, FDE renders the stored information unreadable to unauthorized individuals. This measure is particularly useful if a device gets lost or stolen, as it prevents unauthorized access to the data, ensuring only those with the correct decryption key or password can access the information.

Full-duplex Mode: A type of communication where data transmission can occur in both directions simultaneously. This means that devices can send and receive signals at the same time, similar to a telephone conversation where both parties can talk and listen simultaneously. Full-duplex systems, therefore, double the capacity of a communication channel, as data does not need to be sent in a singular direction at a time, unlike half-duplex systems where communication can only go one way at any given moment. Full-duplex mode is commonly used in various telecommunications and computing scenarios to improve the efficiency of communication channels.

Full Economic Life Cycle: The complete series of stages that an asset, product, or service goes through from creation to its final use or disposal. This includes design, production, distribution, operation and maintenance, and finally, disposal or recycling. The full economic life cycle accounts for all costs and revenues associated with the asset over its entire lifetime and is used for the comprehensive assessment of the total cost of ownership, environmental impact, and value generation. It's a concept used in economics, finance, and sustainable development to evaluate the long-term economic, environmental, and social outcomes of investments or business strategies.

Full Interruption test: A type of disaster recovery testing that involves simulating a complete shutdown of the systems in question to assess how well an organization can recover its operations and continue business processes under such circumstances. This is the most thorough form of testing an organization's resilience to disruptive events. However, it can be risky and disruptive, as it involves halting production systems and can lead to data loss or other adverse effects if not carried out correctly.