Here's a box diagram for an example IFF file, a raster image FORM ILBM. This FORM contains a bitmap header property chunk BMHD, a color map property chunk CMAP, and a raster data chunk BODY. This particular raster is 320 x 200 pixels x 3 bit planes uncompressed. The "0" after the CMAP chunk represents a zero pad byte; included since the CMAP chunk has an odd length. The text to the right of the diagram shows the outline that would be printed by the IFFCheck utility program for this particular file. +----------------------------+ | | | "FORM" 24070 | FORM 24070 ILBM | | - +----------------------------+ | | | | | "ILBM" | | | | | | +----------------------+ | | | | "BMHD" 20 | | .BMHD 20 | | |----------------------| | | | | 320, 200, 0, 0, 3, | | | | | 0, 0, 0, .... | | | | +----------------------+ | | | | 24070 < | +----------------------+ | bytes | | | "CMAP" 21 | | .CMAP 21 | | |----------------------| | | | | 0, 0, 0; 32, 0, 0; | | | | | 64, 0, 0 ... | | | | +----------------------+ | | | 0 | | | +----------------------+ | | | | "BODY" 24000 | | | | |----------------------| | .BODY 24000 | | | 0, 0, 0.... | | | | +----------------------+ | | | | -- +----------------------------+ This second diagram shows a LIST of two FORMs ILBM sharing a common BMHD property and a common CMAP property. Again, the text on the right is an outline á la IFFCheck. +------------------------------+ | "LIST" 48114 | +------------------------------+ | | | "ILBM" | | | | +------------------------+ | | | "PROP" 62 | | .PROP 62 ILBM | +------------------------+ | | | | | | | "ILBM" | | | | +--------------------+ | | | | | "BMHD" 20 | | | ..BMHD 20 | | |--------------------| | | | | | 320, 200, 0, 0, 3,| | | | | | 0, 0, 0, .... | | | | | +--------------------+ | | | | | | | | +--------------------+ | | | | | "CMAP" 21 | | | ..CMAP 21 | | |--------------------| | | | | | 0, 0, 0; 32, 0, 0;| | | | | | 64, 0, 0 .... | | | | | +--------------------+ | | | | 0 | | | +------------------------+ | | | | | | +------------------------+ | | | "FORM" 24012 | | .FORM 24012 ILBM | +------------------------+ | | | | | | | "ILBM" | | | | +--------------------+ | | | | | "BODY" 24000 | | | ..BODY 24000 | | |--------------------| | | | | | 0, 0, 0.... | | | | | +--------------------+ | | | +------------------------+ | | | | | | +------------------------+ | | | "FORM" 24012 | | .FORM 24012 ILBM | +------------------------+ | | | | | | | "ILBM" | | | | +--------------------+ | | | | | "BODY" 24000 | | | ..BODY 24000 | | |--------------------| | | | | | 0, 0, 0.... | | | | | +--------------------+ | | | +------------------------+ | | | | | +------------------------------+