The Lump side has several data structures that represent raw data on disk. Use this to load Wad files from disk and use them as Wads. You may also twiddle bits and other low level stuff as this part of the library exposes the guts of a Wad file.
The WadEntry side reads in raw data and formats it into easy to use data structures that represent specific Lump types: graphics, sounds, maps, and more.
License - Text of the GNU LGPL license, under which libdoomwad is licensed.
Programming Issues - Information and issues relating to how libdoomwad is coded, stuff you need to know if you want to add any functionality, etc.
Coding Standards - Coding standards for libdoomwad.
Source Ports - Information dealing with source port extensions, such as Boom extensions, ZDoom scripting as it related to wad editing, etc.
Wad Resources - Specific information dealing with the wad file format and the format of the resources inside it.
1.4.0