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+#### jlColorT
+Contains a single palette entry in IIgs format.  JoeyLib colors are specified with 4 bit RGB values.
+
+#### jlPixelPairT
+Represents a pair of pixels.  On the IIgs, pixels are stored as 4 bit values with two pixels per byte.  This structure provides easy access to the `l`eft and `r`ight pixels.
+
+#### jlSoundT
+The actual contents of this structure changes depending on which platform the application is running on.  It is intended to be used as a handle for tracking and playing loaded sound effects.
+
+#### jlStaT
+In-memory representation of a static image file.
+
+#### jlStackT
+Stack data type for use with the stack utility functions.
+
+#### jlVecT
+In-memory representation of a vector image file.