x is by default interpreted as AngleBracket[x].
Used in the form x to indicate expected or average value.
Called bra in quantum mechanics.
Used in the form x, y to indicate various forms of inner product.
Used in the form x, y, ... to denote an ordered set of objects.
Not the same as \[RawLess].
Extensible character; grows by default to limited size.
See The Mathematica Book: Section 3.10.4.
See also: \[RightAngleBracket] , \[LeftFloor] , \[LeftCeiling] .