No flash player!

∀ [universal quantification]
∝ [proportionality]
± [plus-minus]
⇒ [material implication]
⊇ [superset]
⊕ [exclusive]
∅ [empty set]
≠ [inequation]
≈ [approximately equal]
∞ [infinity]
∃ [existential quantification]
∑ [summation]