An archive file is a collection of different folders and files that are packaged together so that they can be easily moved from one computer to another. Since many people use this method for backup purposes, it has gained the name "archive." Further, most archive files are compressed in order to save disk space or network bandwidth. A compressed archive must be decompressed before the files inside can be used.
By far the most popular archive type -- the one that Express Zip creates -- is a zip file, which has the ".zip" file extension.
In addition to creating zip files, Express Zip can open and extract the following file formats: