Zip API Reference
Compress files and folders into a zip file and extract it.
The web browser can down load a single file at once. If you have to download several files at once, you have to archive the files into a zip archive file.The zip archive function can also archive the folder. Therefore on actual case, the program copies necessary files into a folder and archive it.
Compress $compressDir directory into $compressFile.
Extract zip file $extractFile into the directory $extractDir.