monline

I'm quite a novice to MacOS so it's no wonder that I've never heard of resource forks before. There's a detailed article on the subject over at Wikipedia. To cut it short: resource forks are data stuctures bound to files in the filesystem. They can contain anything from small strings to large files. Eg. in Windows the icon of executables is stored "inside" the EXE file ... on MacOS these icons can be stored in resource forks.