Notation field notes

Approximately Symbol Blog

Clear, sourced guides to mathematical relation symbols and input methods.

Oct 7, 2026

Congruent Symbol ≅: Meaning, Copy and Codes

Learn the congruent symbol ≅, its geometric meaning, and copy U+2245 plus HTML and LaTeX codes.

Oct 1, 2026

Learn the triple equal sign ≡: what it means in math and logic, how it differs from = and ≈, plus copy, Unicode, HTML, LaTeX and typing codes.

Sep 27, 2026

Learn tilde in LaTeX: when ~ is a non-breaking space, how to print a text tilde, and when to use \sim, \tilde, or \widetilde.