What is the term for an error when a value exceeds the allowed range?

• A. Boundary error
• B. Overflow
• C. Range error
• D. Underflow

Answer: (A)

Exceeding the limits of what a value can represent is called overflow. When a calculation or assignment produces a result larger than the maximum (or smaller than the minimum) that a fixed-width type can hold, the value can wrap around or trigger an error depending on the language. For example, adding 1 to the maximum value of an 8-bit unsigned integer wraps to 0, and in floating-point, an extremely large result may become infinity. Underflow is the opposite idea, referring to results that are too small in magnitude to be represented (often becoming subnormal or zero). Boundary error typically refers to accessing data outside memory or array bounds, not the numeric range of a type. Range error is a more general term for values outside a defined domain, but the standard term for exceeding a type’s representable range is overflow.