# In Your Textbook: Big-O, Big-Θ and Big-Ω

What a Data Structures textbook means by Big-O, Big-Theta and Big-Omega, how to read each symbol aloud, and its formal definition of Big-O in everyday words, checked with a little code.

![Cheat sheet: In Your Textbook: Big-O, Big-Θ and Big-Ω](https://fsdtrainingmedia.blob.core.windows.net/public/images/2026/11/1a07a77d69234bd28a731ef6ead04b69.webp)

- Category: Data Structures
- Level: Journeyman
- Tags: Asymptotic Notation, Big-O Notation, Big-Omega Notation, Big-Theta Notation, software-development
- Updated: November 3, 2026

Source: https://www.ask-codey.com/cheat-sheets/big-o-in-your-textbook-cheat-sheet