Edge Case
/ej kās/
noun — "the weird input nobody expected until it broke everything."
An Edge Case is an unusual, extreme, rare, or unexpected condition that occurs at the outer limits of a system's intended operation. While most software is designed around common inputs and predictable workflows, edge cases live at the fringes where assumptions begin to fail and hidden weaknesses become visible.
Range
/reɪndʒ/
noun — “the span between what a system can hold and what it quietly refuses to remember.”
Range in computing is the set of values that can be represented within a given numeric system, data type, or storage format. It defines the lower and upper bounds of representable numbers before phenomena like overflow or underflow occur.