Common set-theory symbols include ∈ (element of), ∉ (not an element of), ⊂ (proper subset in many conventions), ⊆ (subset or equal), ∪ (union), ∩ (intersection), ∅ (empty set) and ℝ (real numbers). In Word, insert them using Insert > Symbol or the equation editor. Symbols can have convention-dependent meanings, so define ambiguous notation. These set symbols helps to represent mathematical ideas in a concise way and saves space and… Read More »Set Symbols in Word: Meaning, Unicode and Insertion Shortcuts