# Why the Library Check Slows Down and Play Doesn't: O(1) and O(n)

Tell a job whose work stays the same as the library grows from one whose work grows with it, and read their growth rates aloud: O(1), constant time, and O(n), linear time.

![Cheat sheet: Why the Library Check Slows Down and Play Doesn't: O(1) and O(n)](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/11/bbdde428a09b439c84ae295b8719057a.webp)

- Category: Data Structures
- Level: Novice
- Tags: Big-O Notation, Constant Time, Linear Time, software-development
- Updated: November 3, 2026

Source: https://www.ask-codey.com/cheat-sheets/big-o-constant-and-linear-cheat-sheet