Manupulating Images and all their Properties

gimpchannel - Functions for manipulating channels.
gimpcolor - Functions for manipulating color.
gimpconvert - Conversions between RGB, indexed, and grayscale modes.
gimpdisplay - Functions to create, delete and flush new displays (views) on an image.
gimpdrawable - Functions to manipulate drawables.
gimpdrawabletransform -
gimpedit - Edit menu functions (cut, copy, paste, clear, etc.)
gimpfileops - File operations (load, save, etc.)
gimpfloatingsel - Functions for removing or attaching floating selections.
gimpguides - Functions for manipulating guides.
gimpimage - Operations on complete images.
gimplayer - Operations on a single layer.
gimppaths - Operations related to paths.
gimppixelfetcher - Functions for operating on pixel regions.
gimppixelrgn - Functions for operating on pixel regions.
gimpregioniterator - Functions to traverse a pixel regions.
gimpselection - Functions for manipulating selections.
gimptexttool - Functions for controlling the text tool.
gimptile - Functions for working with tiles.
gimptools - Access to common toolbox tools.
gimpundo - Control of undo/redo.