\[ExponentialE] (Mathematica Character Name)

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.

\[ImaginaryI] (Mathematica Character Name)

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

\[ImaginaryJ] (Mathematica Character Name)

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.

\[Implies] (Mathematica Character Name)

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 ...

\[Intersection] (Mathematica Character Name)

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 ...

\[InvisibleApplication] (Mathematica Character Name)

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

\[InvisibleComma] (Mathematica Character Name)

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 ...

\[LeftArrow] (Mathematica Character Name)

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 ...

\[LeftBracketingBar] (Mathematica Character Name)

Unicode: F603. Alias: Esc l| Esc. Matchfix operator.  x  is by default interpreted as BracketingBar[x]. Used in mathematics to indicate absolute value (Abs), determinant ...

\[LeftDoubleBracketingBar] (Mathematica Character Name)

Unicode: F605. Alias: Esc l|| Esc. Matchfix operator.  x  is by default interpreted as DoubleBracketingBar[x]. Used in mathematics to indicate taking a norm. Sometimes used ...