Hyperlink creates a hyperlink to a specified cell, notebook, or URL.
CommonDefaultFormatTypes -> {opt_1 -> val_1, opt_2 -> val_2, ...} is an option that specifies default formats for newly created cells.
CopyFile["file_1", "file_2"] copies file_1 to file_2.
DefaultBoxStyle is a low-level option for three-dimensional graphics functions that specifies the default style to use in rendering the bounding box.
DefaultFaceGridsStyle is a low-level option for 3D graphics functions that specifies the default style to use in rendering face grids.
DefaultFieldHintStyle is a low-level option for InputField that specifies the default style to use for displaying the field hint.
DefaultFrameTicksStyle is a low-level option for 2D graphics functions that specifies the default style to use in rendering frame ticks.
DefaultGridLinesStyle is a low-level option for 2D graphics functions that specifies the default style to use in rendering grid lines.
DefaultLabelStyle is a low-level option for formatting and related constructs that specifies the default style to use in displaying their label-like elements.
DirectoryStack[] gives the directory stack that represents the sequence of current directories used.