Compare it

Compare is a simple sounding notion. The most commonly neglected requirement is what exactly is to be compared.

The most fundamental question is whether you are comparing files that should be the same or files that are different but contain the same information. The solution obviously are very different. The simplest compare is a file compare but it only works if the files are expected to be identical. Even a single line in a different place can cause some havoc. This brings you into the realm of comparing miscellaneous files.

Miscellaneous file comparisons normally require some level of customization. If the files are tabular, then a simple mapping may meet the needs. However, throw in a degree of irregular ordering and the cute little kitten becomes a temperamental demon.