Binary search is a fast algorithm for finding the position of a value within a sorted array. It reflects the way people intuitively “guess numbers” by repeatedly asking “Is your number bigger or smaller than x?”

• v1.0: Initial version
• v1.1: Update the IDEA logo

Initially published 2018-02-14.

IDEA is a series of nonverbal algorithm assembly instructions, developed by Sándor P. Fekete and blinry. The instructions explain how various popular algorithms work, entirely without text. This also allows the instructions to be understood interculturally.

All instructions are available under Creative Commons licenses, so everyone is free to share and adapt them in noncommercial settings. We hope they will be useful in all sorts of contexts, for teachers, students, and curious people alike. Visit the about page to learn more, or download all instructions as a PDF.