HotellingTSquareDistribution[p, m] represents Hotelling's T^2 distribution with dimensionality parameter p and m degrees of freedom.
"Introduction to Manipulate" and "Introduction to Dynamic" provide most of the information you need to use Mathematica's interactive features accessible through the functions ...
FlipView[{expr_1, expr_2}] represents an object which flips between displaying expr_1 and expr_2 each time it is clicked.FlipView[{expr_1, expr_2, ...}] cyclically flips ...
Ticks
(Built-in Mathematica Symbol) Ticks is an option for graphics functions that specifies tick marks for axes.
Selectable is an option for displayed objects, cells, and notebooks that specifies whether their contents can be selected interactively using the front end.
SubMinus[expr] displays as expr_-.
SubPlus
(Built-in Mathematica Symbol) SubPlus[expr] displays as expr_+.
InputAliases is an option for cells and notebooks which specifies additional Esc\[ThinSpace]name\[ThinSpace]Esc aliases to be allowed on input.
Unitize
(Built-in Mathematica Symbol) Unitize[x] gives 0 when x is zero, and 1 when x has any other numerical value.
MATHEMATICA HOW TO Tutorials » Notebooks as Documents Doing Computations in Notebooks Options for Notebooks Options for Cells Two-Dimensional Expression Input Entering ...