Big-O Notation

**Semantic type:** Conceptual Entity

**Definition:** A theoretical measure of the execution of an algorithm, usually the time or memory needed, given the problem size n, which is usually the number of items; a mathematical notation used to describe the asymptotic behavior of functions. More precisely, it is used to describe an asymptotic upper bound for the magnitude of a function in terms of another, usually simpler, function. (from NIST)