Big O notation ($O(n)$)

The relation $f(x)=O(g(x))$ near a limit point means that $|f(x)|\le C|g(x)|$ there for some constant $C$.

Big O notation is a mathematical concept used to describe the performance or complexity of an algorithm in terms of time or space requirements as the input size grows. It provides a high-level understanding of how the runtime or space requirements of an algorithm scale with increasing input sizes, allowing for a general comparison between different algorithms. In Big O notation, we express the upper bound of an algorithm's growth rate, ignoring constant factors and lower-order terms.