A 002 file is the second part of a split archive created by various file splitter and joiner applications. It contains the data sequentially following the data stored in a .001 file. 002 files may also have corresponding files with the extensions .003, ".004," etc.
File splitting and joining utilities are useful for segmenting large files into smaller pieces so they can be copied to CDs or emailed in manageable parts. While the ".001," ".002," etc. extensions are commonly used, not all of them use the same file format. Therefore, be sure to check the software that originally created the file.