ex=Exp[1/x^2+Sin[x^2]]

ex/.{a_^b_->b^a}

ex//TreeForm

TreeForm/@{ex,Replace[ex, a_^b_->b^a,{0}]}

ex

Replace[ex, a_^b_->b^a,{0,1}]

Depth[ex]

ex/.{a_^b_->{a,b}}

ex//.{a_^b_->{a,b}}

ReplaceAll

Replace

ReplaceList

ReplaceRepeated

a+x+y//.{x->a,y->x,a->y}

2a+x

MatchQ[ex, a_^b_]

?Cases

Cases[ex, a_^b_,{0,Depth[ex]}]

Position[ex, a_^b_,{0,Depth[ex]}]

Position[ex, a_^(b_+c_),{0,Depth[ex]}]

ex//FullForm

ex//FullForm

ex//TreeForm

a+Transpose[{{3,c,Pi,a}}]

Attributes[Plus]

ClearAttributes[Plus,Protected]

ClearAttributes[Plus,Listable]

Attributes[Plus]

a+{2,a,3}

Transpose[v={{a},{b}}]//MatrixForm

v//MatrixForm

Part2x2[A_String,args___/;MemberQ[{args},"Triangular"|"LowTri"]]:=
{{A<>"TL",Zero},
{A<>"BL",A<>"BR"}}

Part2x2[A_String]:=
{{A<>"TL",A<>"TR"},
{A<>"BL",A<>"BR"}}

Part2x2["M","Triangular"]

Part2x2["K",blah]

Part2x2["K"]

f[M:{{_,b_},l:{_,_}}]