Unicode: F74D. Alias: Esc ee Esc. Letter-like form with built-in value.  is interpreted by default as the symbol E, representing the exponential constant.

Unicode: F74E. Alias: Esc ii Esc. Letter-like form with built-in value.  is interpreted by default as the symbol I, representing Sqrt[-1].

Unicode: F74F. Alias: Esc jj Esc. Letter-like form with built-in value.  is interpreted by default as the symbol I, representing Sqrt[-1]. Used in electrical engineering.

Unicode: F523. Alias: Esc => Esc. Infix operator with built-in evaluation rules. x  y is by default interpreted as Implies[x,y]. x  y  z groups as x  (y  z). Not the ...

Unicode: 222B. Alias: Esc int Esc. Compound operator with built-in evaluation rules. ∫ f  x is by default interpreted as Integrate[f,x]. ∫_a^b f  x is by default ...

Unicode: 22C2. Alias: Esc inter Esc. Infix operator with built-in evaluation rules. x ⋂ y is by default interpreted as Intersection[x,y]. The character ⋂ is sometimes called ...

Unicode: F76D. Alias: Esc @ Esc. Structural element with built-in meaning. \[InvisibleApplication] is by default not visible on display, but is interpreted as function ...

Unicode: F765. Alias: Esc , Esc. Structural element with built-in meaning. \[InvisibleComma] is by default not visible on display, but is interpreted on input as an ordinary ...

Unicode: 2329. Alias: Esc < Esc. Matchfix operator. ⟨ x ⟩ is by default interpreted as AngleBracket[x]. Used in the form ⟨x ⟩ to indicate expected or average value. Called ...

Unicode: 2190. Alias: Esc <- Esc. Infix arrow operator. x ← y is by default interpreted as LeftArrow[x,y]. Sometimes used in computer science to indicate assignment: x gets ...