This document provides information about electron configuration. It begins by defining electron configuration as the arrangement of electrons in an atom's orbitals, which is described using quantum numbers. It then discusses the three main rules for writing electron configurations: 1) Aufbau principle, which states that electrons fill the lowest available energy levels first, 2) Pauli exclusion principle, which limits each orbital to two electrons of opposite spin, and 3) Hund's rule, which states that degenerate orbitals will fill with one electron each before pairing. The document provides examples of writing full and condensed electron configurations and drawing orbital diagrams for various elements. It includes an activity for students to practice these skills.