Final answer:
A logic bomb is a type of malicious code added to a legitimate program that activates under specific conditions, such as a particular date or event.
Step-by-step explanation:
The type of computer code that is typically added to a legitimate program but remains dormant until a specific logical event triggers it is known as a logic bomb. Unlike a virus, which reproduces by attaching to other programs, or a worm, which replicates itself to spread to other computers, a logic bomb does not reproduce. It's a piece of malicious code inserted intentionally into a legitimate program, set to 'explode' or trigger a malicious function when certain conditions are met, such as a specific date and time, or the deletion of an employee's payroll record. Logic bombs can be very damaging, potentially deleting files or data when activated.