Inner
(Built-in Mathematica Symbol) Inner[f, list_1, list_2, g] is a generalization of Dot in which f plays the role of multiplication and g of addition.
Inpaint
(Built-in Mathematica Symbol) Inpaint[image, region] retouches parts of image that correspond to nonzero elements in region.
InputAliases is an option for cells and notebooks which specifies additional Esc\[ThinSpace]name\[ThinSpace]Esc aliases to be allowed on input.
InputAssumptions is an option for WolframAlpha that specifies assumptions for current query input.
InputAutoReplacements is an option for cells and notebooks which specifies strings of characters that should be replaced immediately on input.
InputField[] represents a blank editable input field. InputField[x] represents an editable input field that currently contains the expression x. InputField[Dynamic[x]] takes ...
InputForm[expr] prints as a version of expr suitable for input to Mathematica.
InputNamePacket[string] is a MathLink packet that contains in string the name to be assigned to the next input.
Input
(Built-in Mathematica Symbol) Input[] interactively reads in one Mathematica expression. Input[prompt] requests input, displaying prompt as a "prompt".Input[prompt, init] in a notebook front end uses init ...
InputNotebook[] gives the current notebook into which keyboard input in the front end will be directed.